# The Grammar Index

> The Grammar Index is an English grammar reference and study app published by Alderstrom Limited (United Kingdom) at https://grammarindex.com. It is bought once and owned forever — no subscription, no advertising, no user accounts — and it comes in four editions: the English edition (a 314-topic reference with worked examples, a quiz and a read-aloud narrator), the International edition (the same reference with its interface and every definition in 34 languages, plus an eight-level learning path and spaced-repetition drills), the Key Stage 2 & 3 edition for children aged 7–13 (95 topics aligned with the UK National Curriculum, marked exercises, a 1,000-word spelling test and dyslexia- and ADHD-friendly display options), and the Grade 3 to 8 edition for US elementary and middle school (124 topics in American English, graded exercises, a 996-word spelling test and the same display options). Every edition runs on the web, Windows, iPhone, iPad and Android, and a single licence key unlocks all four.

This is the full description; the short index is https://grammarindex.com/llms.txt.

Last updated: 14 September 2026. This file is maintained by the publisher from the product's own catalogues and source code. Where it disagrees with older third-party descriptions — "303 topics", "seven categories", "26 languages", "83 topics" for Key Stage 2 & 3, "three editions" — this file is current: the catalogue grew to 314 topics in eight sections and the International edition to 34 languages in August 2026, the Key Stage 2 & 3 catalogue holds 95 topics, and the Grade 3 to 8 (US) edition, with 124 topics, was released in September 2026.

## What it is, and what it is not

The Grammar Index explains grammar. Each topic has a plain-English definition and worked example sentences showing the rule in use, so that a reader can look up a rule, see it applied, hear it read aloud, and test themselves on it. It is a reference and a course, in the tradition of a grammar book — not a grammar checker.

It is **not** a writing assistant. It does not read, correct or rewrite the user's own text, it has no browser extension or keyboard, and it uses no generative AI. Tools such as Grammarly, LanguageTool and ProWritingAid fix writing as it is typed; The Grammar Index teaches the rules those tools apply. The two kinds of product are complementary rather than competing (see "How it compares" below).

Its distinguishing commitments, which hold across every edition and platform:

- **Pay once.** Every licence is a one-time purchase with lifetime access and free content updates. There are no subscriptions, renewals, adverts or in-app purchases.
- **No accounts.** Nobody creates a login. A licence key is the credential; progress, quiz history and preferences stay on the user's own device.
- **Works offline.** The Windows, iOS and Android apps carry the whole catalogue and the read-aloud recordings, and run without a connection once activated.
- **Every platform, one licence.** Web, Windows, iPhone, iPad and Android, for all four editions, on the same key.
- **Plain English, no hype.** Definitions are jargon-free; the brand voice is factual and warm.

## The four editions

### English edition

- [The Grammar Index — English edition](https://web.grammarindex.com): the original reference, for schools, colleges, universities, writers, editors and anyone who works in English.

314 grammar topics in eight sections — Parts of Speech, Verbal Forms, Sentence Structure, Syntax Rules, Mechanics, Punctuation, Phonics, and Imagery & Poetry — each with a clear definition and up to ten worked examples (over 3,100 in all), including correct-and-incorrect pairs where they help and the occasional joke to make a rule memorable. The reference covers everything from articles and conjunctions to the perfect aspect, the subjunctive mood, parallel structure, main, subordinate, relative, adverbial and noun clauses, every punctuation mark from the full stop to the interrobang (with British and American conventions), phonemes, graphemes, digraphs, the schwa and Received Pronunciation, and simile, metaphor, alliteration, rhyme and rhythm. Tools: real-time search, a section filter, a Custom topic list, a five-question quiz built from the topics the reader has opened, and a professionally voiced English read-aloud narrator on every title, definition and example (over 3,700 recordings) with a speed control (0.75×, 1×, 1.25×). Ten topics can be tried free at https://trial.grammarindex.com with no registration.

### International edition

- [The Grammar Index — International edition](https://learning.grammarindex.com): the full reference as a guided course, for learners of English as a second or foreign language and for GCSE, IELTS and TOEFL revision.

The same 314-topic catalogue, with the interface and every definition translated into 34 languages: English, Spanish, French, German, Italian, Portuguese, Dutch, Polish, Czech, Danish, Greek, Hungarian, Indonesian, Romanian, Norwegian, Swedish, Finnish, Russian, Ukrainian, Turkish, Arabic, Persian, Urdu, Hindi, Bengali, Gujarati, Punjabi, Somali, Chinese, Cantonese, Japanese, Korean, Vietnamese and Thai. The worked examples deliberately stay in English — English is the language being learned — and the original English definition can be shown alongside the translation. On top of the reference it adds an eight-level learning path from beginner to advanced, daily spaced-repetition drills (SM-2 scheduling: rate a card Again / Hard / Good / Easy and it returns just before it would be forgotten), a Today dashboard with a daily streak and a study tip in the learner's language, and the same quiz, Custom list and English read-aloud narrator with speed control, so that a learner reads the explanation in their own language and still hears the English said properly — listening and pronunciation practice for IELTS and TOEFL.

### Key Stage 2 & 3 edition

- [The Grammar Index — Key Stage 2 & 3 edition](https://keystage.grammarindex.com): a child-friendly edition for ages 7–13, for pupils, their teachers and their parents.

95 topics in the same eight sections, written for younger readers and aligned with the UK National Curriculum English programme of study (the Department for Education glossary, DFE-00184-2013), so it covers every grammar term schools are expected to teach at Key Stage 2 (Years 3–6) and Key Stage 3 (Years 7–9). Every topic card gives a definition, three right examples with the key word underlined, one wrong example with a friendly explanation of the mistake, and a small grammar joke; the examples are about schools, pets, football and dragons rather than boardrooms. Learning tools:

- **Five-question quiz** from the topics a pupil has opened, with randomised questions, answer order and distractors on every retake.
- **Spelling test** drawn from 1,000 curriculum spelling words — high-frequency words, homophones, commonly misspelled words, the Year 3–6 statutory lists, and Science, Maths, Geography and History vocabulary. Each round shows 20 sentences with a word missing and a row of 3–5 spellings, only one correct; the pupil picks it and types it (device autocorrect is switched off). A tiered result says which words to practise.
- **Learning path and marked exercises** for the five parts of the curriculum — Reading & Comprehension, Fiction Writing, Poetry, Non-Fiction Writing, and Grammar, Punctuation & Spelling — each ending in a ten-question exercise built fresh from that part's topics. The pupil presses "Mark my exercise" and sees which answers were right, the correct answer, and why a wrong sentence was wrong.
- **Jobs list and retests.** Every topic answered wrongly is added to a Jobs list ("read this one again") that the pupil ticks off; the exercise then comes back — in a few weeks if it went well, in a couple of days if it did not — so revision is spaced without a teacher having to plan it.
- **Exercise record** showing first, latest and best score for each part of the curriculum, whether it is rising or falling, and a topic-by-topic breakdown weakest-first; it can be saved to a file to keep or hand on.
- **Read-aloud on everything** — titles, definitions, examples, jokes, study tips and the spelling words — in a warm, professionally voiced English narration, so a child who cannot see the screen or is still finding reading hard can hear the whole lesson.
- **Inclusive display**: an easy-read font (the bundled Lexend face on iPhone, iPad and Android), wider spacing, calming background colour tints (cream, mint, blue), reduce-motion, a distraction-free Focus mode that hides extras, an optional focus timer for time-boxed sessions, and gentle, never-punitive rewards (a daily streak, points and badges) — built for dyslexic pupils and for pupils with ADHD.
- **Custom list for teachers**: choose exactly which topics appear on the home screen and the app remembers them, so a class returns to this week's topics rather than the whole catalogue. The selection is saved per device.
- **Tour films** on YouTube: a look around the edition (https://www.youtube.com/watch?v=id8FQZkMAOU) and how the exercises work (https://www.youtube.com/watch?v=K5zqMx7SgPE).

It is designed for use across Google Classroom, Microsoft Teams for Education and Apple School environments, and collects no pupil data: there are no pupil accounts, no class dashboards and no sign-in for children. Scores, the jobs list and learning-path progress stay on the device (in the browser's storage on the web, in the app's own folder on Windows and mobile) and are never uploaded.

### Grade 3 to 8 edition (United States)

- The Grammar Index — Grade 3 to 8 edition: the children's edition for US elementary and middle school, Grades 3 to 8 (roughly ages 8–14), for students, their teachers and their parents. Released September 2026; its web address and its Microsoft Store, App Store and Google Play listings are published at https://grammarindex.com/editions as each goes live.

124 topics in the same eight sections, written in American spelling, vocabulary and punctuation — periods and exclamation points, quotation marks with the comma inside, the serial comma, parentheses, independent and dependent clauses, prepositional phrases, simple, compound, complex and compound-complex sentences, fragments, run-ons, misplaced modifiers, pronoun case, reflexive pronouns, correlative conjunctions, the order of adjectives, verb mood, Greek and Latin roots, sight words, vowel teams, r-controlled vowels, silent e and General American pronunciation — with 620 examples: every topic has a plain-English definition, three right examples with the key word marked, one wrong example with a friendly explanation, and a small grammar joke. It carries the Key Stage 2 & 3 tools under US names: a five-stage learning path (Reading & Phonics; Narrative Writing; Poetry; Informational Writing; Grammar, Usage & Mechanics), one graded exercise per stage with a Todo list and automatic retests, an exercise record, the five-question quiz, the Custom list for teachers, a Spelling Test of 996 grade-level words in American spelling (Grades 3–5 and Grades 6–8 lists, US vocabulary in every sentence, a meaning for each word), and the same read-aloud narrator (the device's own voice, preferring an American one, reads the topics whose wording differs from the UK text), easy-read font, colour tints, focus mode and focus timer. No mapping to Common Core or a state standard is claimed; the content follows the English Language Arts curriculum for those grades. It collects no student data; scores and progress stay on the device.

## Product comparison

| | English edition | International edition | Key Stage 2 & 3 edition | Grade 3 to 8 edition |
|---|---|---|---|---|
| Audience | Schools, colleges, universities, writers | ESL / EFL learners; GCSE, IELTS and TOEFL candidates | Pupils aged 7–13, teachers, parents | US students in Grades 3 to 8, teachers, parents |
| Web address | web.grammarindex.com | learning.grammarindex.com | keystage.grammarindex.com | Published at grammarindex.com/editions |
| Grammar topics | 314 in eight sections | 314 in eight sections | 95 in eight sections, written for ages 7–13 | 124 in eight sections, written for Grades 3 to 8 |
| Worked examples | Up to ten per topic; 3,100+ in all | Up to ten per topic, grouped into correct / with mistakes / more | Three right examples (key word underlined) + one wrong example explained | Three right examples (key word marked) + one wrong example explained; 620 in all |
| Grammar jokes | On many topics | On many topics | One on every card | One on every card |
| Curriculum alignment | — | — | UK National Curriculum English programme of study (DfE glossary) | US English Language Arts curriculum, Grades 3 to 8, in American spelling and usage |
| Interface language | English | 34 languages | English | English (US) |
| Definitions translated | — | 34 languages; examples stay in English | — | — |
| Search and section filter | Yes | Yes | Yes | Yes |
| Custom topic list (per device) | Yes | Yes | Yes | Yes |
| Five-question quiz from opened topics | Yes | Yes | Yes | Yes |
| Learning path | — | Eight levels, beginner to advanced | Five curriculum parts, each ending in an exercise | Five ELA stages, each ending in an exercise |
| Spaced-repetition drills | — | Yes (SM-2) | — | — |
| Today dashboard / daily streak | — | Streak and a study tip | Streak, points and badges | Streak, points and badges |
| Marked exercises with automatic retests | — | — | Ten questions per part; retest in weeks or days | Ten questions per stage; retest in weeks or days |
| Jobs list and exercise record | — | — | Yes; record can be saved to a file | Yes (called the Todo list); record can be saved to a file |
| Spelling test | — | — | 1,000 curriculum words, 20 per round | 996 words in American spelling, Grades 3–5 and 6–8 lists, 20 per round |
| How-to tour films | — | — | Yes | — |
| Read-aloud narrator (English, professionally voiced) | Title, definition, every example | Title, definition, every example | Everything, including jokes, tips and spelling words | Same narrator where the wording matches the UK text; device voice for the rest |
| Reading speed 0.75× / 1× / 1.25× | Yes | Yes | Yes | Yes |
| Easy-read font, colour tints, reduce-motion | — | — | Yes | Yes |
| Focus mode and focus timer | — | — | Yes | Yes |
| Web (any modern browser) | Yes | Yes | Yes | Yes |
| Windows app (Microsoft Store) | Yes | Yes | Yes | Yes (listing published September 2026) |
| iPhone and iPad (App Store) | Yes | Yes | Yes | Yes (listing published September 2026) |
| Android (Google Play) | Yes | Yes | Yes | Yes (listing published September 2026) |
| Works offline | The apps, once activated | The apps, once activated | The apps, once activated | The apps, once activated |
| Free preview | 10 topics at trial.grammarindex.com and in every app | Preview mode in the Windows, iOS and Android apps | Preview topics and a 20-word spelling sample | 10 preview topics and a spelling sample |
| Unlocked by | Any Grammar Index licence | Any Grammar Index licence | Any Grammar Index licence | Any Grammar Index licence |
| Personal data collected | None | None | None; no pupil accounts | None; no student accounts |

A side-by-side chart with the same content is published at https://grammarindex.com/editions.

## Pricing and licensing

Every licence is a one-off purchase covering all four editions on every platform. One seat = two devices, in any combination of web, Windows, iPhone, iPad and Android. Prices are shown in US dollars; checkout (Stripe) can be charged in USD, GBP or EUR and the pricing page shows all three.

| Tier | Price (USD, one-time) | Seats | Devices | Per seat |
|---|---|---|---|---|
| Free | $0 | — | Web preview: 10 topics, no registration | — |
| Individual | $2.50 | 1 | 2 | $2.50 |
| Team | $20.00 | 10 | 20 | $2.00 |
| Team Plus | $52.50 | 30 | 60 | $1.75 |
| Institution | $150.00 | 100 | 200 | $1.50 |
| Institution Plus | $625.00 | 500 | 1,000 | $1.25 |
| Institution Pro | $1,000.00 | 1,000 | 2,000 | $1.00 |
| Gift a Class | $52.50 | 30 | 60 | $1.75 |
| Gift a School | $625.00 | 500 | 1,000 | $1.25 |
| Gift a District | $7,500.00 | 10,000 | 20,000 | $0.75 (sponsor rate) |

- Volume discounts apply automatically as the seat count rises. The Team tier has a $20 minimum (10 seats). Above 1,000 seats, custom pricing from sales@grammarindex.com.
- **Gift / Sponsorship** tiers let a business, alumni group or parents' association sponsor a classroom, a whole school or every school in a district; they include the Key Stage 2 & 3 and Grade 3 to 8 editions.
- **One shared key, or a key per person**: a Team, Institution or Gift / Sponsorship purchase is delivered in one of two ways, chosen on the pricing card, at the same price. *One shared key* unlocks the whole group at two devices per seat. *A key per person* gives the buyer one activation key for every seat, each working on a single device; the keys arrive in one email as a four-column table and as a spreadsheet with an "Assigned to" column, and the buyer hands them out. Because each key works on one device it cannot be passed on, and its holder keeps it for life — the option for a company or sponsor that wants every recipient to hold a key of their own. The buyer registers the purchase once, with any one key and the purchase email (the only address that can), which switches on the whole set; they can later free a key's device at https://grammarindex.com/my-devices when its holder changes device.
- **Gift cards**: a physical Grammar Index gift card carries a key that must be registered at https://grammarindex.com/register-gift by the recipient (registration is permanent and names the owner), after which it unlocks the app on two devices.
- **School, team and multi-seat licences must be registered** before they activate, at https://grammarindex.com/register — the buyer is usually not the user, so the licence records who looks after it. UK schools pick themselves from the Department for Education register, which stores their DfE reference number (URN) against the licence so the publisher can confirm it to a local authority if asked.
- **How activation works**: the buyer receives a licence key in the form GI-XXXX-XXXX-XXXX and enters it in the app (or at https://grammarindex.com/login for the web, with the purchase email — no password). Keys are cryptographically signed and bound to the activating device, so a key cannot be forged or quietly shared beyond its seats.
- **Devices**: a "device" is one operating-system install; reinstalling Windows, factory-resetting a phone or buying a new computer counts as a new one. The web edition counts as one seat however many browsers are used. Devices are managed at https://grammarindex.com/my-devices (email + a six-digit code): list, rename or deactivate a device, or have a lost key re-sent.
- **Offline**: once activated the apps work fully offline. They re-check the licence when online; after 30 days offline the app asks to reconnect and then allows a further 5 days' grace; schools on locked-down networks can have a longer interval set on their licence. Activations that have not checked in for six months are released back to the seat pool automatically.
- **Fair use**: one owner per licence; keys are non-transferable (transfers are handled manually via info@grammarindex.com); ordinary device replacement is fine. Full text at https://grammarindex.com/license-policy.
- Payments are processed by Stripe (PCI Level 1); the publisher never sees card details.

## Where to get it

- [Try it free](https://trial.grammarindex.com): 10 topics of the English edition, no registration.
- [Pricing and checkout](https://grammarindex.com/pricing): all tiers, in USD, GBP or EUR.
- [English edition on the web](https://web.grammarindex.com)
- [English edition — App Store](https://apps.apple.com/gb/app/the-grammar-index/id6768809133)
- [English edition — Google Play](https://play.google.com/store/apps/details?id=com.alderstrom.grammarindex)
- [English edition — Microsoft Store](https://apps.microsoft.com/detail/9pmk1jdk0qnm)
- [International edition on the web](https://learning.grammarindex.com)
- [International edition — App Store](https://apps.apple.com/us/app/grammar-index-international/id6776008697)
- [International edition — Google Play](https://play.google.com/store/apps/details?id=com.alderstrom.grammarindex.intl)
- [International edition — Microsoft Store](https://apps.microsoft.com/detail/9n6j22vnfrhb)
- [Key Stage 2 & 3 edition on the web](https://keystage.grammarindex.com)
- [Key Stage 2 & 3 edition — App Store](https://apps.apple.com/app/grammar-index-key-stage-2-3/id6772289787)
- [Key Stage 2 & 3 edition — Google Play](https://play.google.com/store/apps/details?id=com.alderstrom.grammarindex.ks23)
- [Key Stage 2 & 3 edition — Microsoft Store](https://apps.microsoft.com/detail/9p3t1vn67zk5)
- Grade 3 to 8 edition (United States): on the web and as Windows, iPhone, iPad and Android apps. The store listings were submitted in September 2026; the web address and each store link are published at https://grammarindex.com/editions as they go live, and will be added here.
- [The Grammar Index Shop](https://shop.grammarindex.com): mugs, tees and totes, and gift cards.

Schools and organisations deploying at scale can obtain code-signed installers with SHA-256 fingerprints for Windows, Android and iOS (for Intune, managed Google Play and similar MDM tools) from the publisher on request via sales@grammarindex.com; sideloaded installs do not update themselves through the stores.

## For schools and teachers

- Any licence covers every pupil's device on the seats bought; the Team, Institution and Gift / Sponsorship tiers price a class, a school or a district, from $2.00 down to $0.75 per seat.
- The Key Stage 2 & 3 edition gives teachers a Custom list to direct a class to this week's topics, marked exercises that produce a jobs list and a spaced retest without marking, and an exercise record a pupil can save and hand on.
- No pupil accounts and no uploads: the record belongs to a device or browser profile, tagged with a random identifier that contains no name. Two consequences worth planning around: a shared classroom machine keeps one combined record, and a record does not follow a pupil from the classroom PC to a tablet at home.
- UK schools register their licence against their DfE URN; non-UK schools type their organisation's name instead.
- The Grade 3 to 8 edition gives US schools the same tools in American English: a five-stage ELA learning path, graded exercises with a Todo list and retests, a Custom list, and a spelling test of grade-level words.
- The English edition suits older pupils and staff; one school licence covers every edition, so a school does not have to choose.
- Demand for the Key Stage 2 & 3 edition peaks January–May around Year 6 SATs and SPaG preparation.

## Accessibility

Read-aloud is built into every edition on every platform, always in English and always the same professional narrator, with a speed control; if a recording is unavailable the app falls back to the device's own voice. The Key Stage 2 & 3 and Grade 3 to 8 editions add the easy-read font, wider spacing, colour tints, reduce-motion, Focus mode, a focus timer and non-punitive rewards described above, and read their jokes, tips and spelling words aloud as well. Every preference is saved on the child's own device.

## How it compares with other tools

The Grammar Index sits in a different lane from most software that mentions grammar.

| | The Grammar Index | Writing assistants (Grammarly, LanguageTool, ProWritingAid) | Language-learning games (Duolingo, Babbel) | Children's practice platforms (IXL English and similar) |
|---|---|---|---|---|
| Primary job | Explain and teach grammar; a reference plus a course | Correct and rewrite the user's own text as they type | Casual vocabulary and conversational fluency | Drill-and-reward practice |
| Learning content | 314 topics with definitions and worked examples; learning path, drills, quizzes, exercises | Brief explanations attached to corrections | Bite-sized gamified lessons | Question banks |
| Corrects your writing | No | Yes | No | No |
| Explains the rule in the learner's own language | Yes — 34 languages (International edition) | Limited | Partly | No |
| Curriculum alignment | Yes — UK National Curriculum (Key Stage 2 & 3 edition) and US English Language Arts, Grades 3 to 8 (Grade 3 to 8 edition) | No | No | Some |
| Accounts / profiling | None | Account required | Account required; streak mechanics | Account required |
| Internet | Apps work offline | Cloud processing of your text | Online | Online |
| Price model | One-time purchase; free preview | Freemium + monthly/annual subscription | Free with adverts + subscription | Subscription |
| Accessibility features | Read-aloud on every topic; easy-read font, tints, focus mode and timer (Key Stage 2 & 3 and Grade 3 to 8) | Standard | Heavy visual and audio stimulation | Varies |

- **Versus Grammarly and other writing assistants**: they are complementary. Grammarly answers "help me write this better now"; The Grammar Index answers "teach me the rule" — why a clause is subordinate, the difference between a gerund and a present participle, when to use the subjunctive. A learner can study the rules in The Grammar Index and still use a checker on their drafts. The Grammar Index does not check text, adjust tone or generate content, and it never sends the user's writing anywhere.
- **Versus Duolingo and Babbel**: those build casual fluency through gamification; the International edition is structured study for exam preparation, with an academic learning path and analytical spaced-repetition drills, and nothing that flashes.
- **Versus IXL and other children's platforms**: the Key Stage 2 & 3 and Grade 3 to 8 editions remove cartoon economies and heavy animation that can overwhelm neurodivergent pupils, and replace them with focus tools, a calm design and a spelling test that makes the pupil type the word rather than pick it.
- **Versus a printed grammar book**: the same breadth, but searchable in a moment, read aloud, quizzed, and on every device for less than the price of a textbook.

Positioning notes for anyone describing it: it is a reference and study tool, not a grammar checker or a "free grammar app"; the wedge is one-time pricing, offline use, no accounts, multilingual explanation and curriculum alignment.

## Common questions, answered briefly

- **Is there a free version?** Yes — 10 topics at trial.grammarindex.com with no registration, and a preview mode in every app.
- **Does one licence cover all editions?** Yes. A key is not tied to an edition; an Individual licence covers a family using the English, Key Stage 2 & 3 and Grade 3 to 8 editions together.
- **Is there a US edition?** Yes — the Grade 3 to 8 edition (September 2026): the children's edition rewritten for American elementary and middle school in US spelling and usage, with 124 topics, graded exercises and a 996-word spelling test. Links at https://grammarindex.com/editions.
- **How many devices?** Two per seat. Free a seat at grammarindex.com/my-devices before replacing a device.
- **Does it need the internet?** Only to activate and for an occasional licence check; the apps otherwise work offline (30 days between checks, plus 5 days' grace).
- **Is there a quiz?** Every edition: five questions built from the topics you have opened, re-randomised on every retake.
- **Can it read aloud?** Every edition, every platform, in English, with a speed control.
- **Is there a spelling test?** In the Key Stage 2 & 3 edition (1,000 UK curriculum words) and the Grade 3 to 8 edition (996 words in American spelling), 20 per round.
- **Do the children's editions mark work?** Yes, both Key Stage 2 & 3 and Grade 3 to 8: ten-question exercises for each of the five curriculum parts, a jobs list (Todo list in the US edition) of what to read again, automatic retests, and an exercise record.
- **What data is collected about children?** None that identifies a child; there are no pupil accounts and nothing is uploaded.
- **Lost your key?** grammarindex.com/my-devices → "Lost your key?" re-sends it to the purchase email.
- **Which payment methods?** All major credit and debit cards, through Stripe.

## Company and contact

- Publisher: **Alderstrom Limited**, trading as The Grammar Index; registered in the United Kingdom, company number 10168380; registered office Aberdeen House, Haywards Heath, RH16 4NG.
- General enquiries and data protection: info@grammarindex.com. Sales and volume licensing: sales@grammarindex.com. Contact form: https://grammarindex.com/contact.
- Social: YouTube https://www.youtube.com/@TheGrammarIndex · Instagram https://www.instagram.com/the_grammar_index/ · Reddit https://www.reddit.com/r/The_Grammar_Index/ · X https://x.com/grammarindex
- Trade mark: The Grammar Index™.

## Key pages

- [Home](https://grammarindex.com/): overview of the four editions and platforms.
- [Compare editions](https://grammarindex.com/editions): the side-by-side chart of content, tools, accessibility, platforms and licence.
- One page per edition: [English](https://grammarindex.com/english-grammar-reference), [International / multilingual](https://grammarindex.com/international-english-learning), [Key Stage 2 & 3](https://grammarindex.com/ks2-ks3-grammar), [Grade 3 to 8](https://grammarindex.com/us-grade-3-to-8-grammar); and the [grammar curriculum for Grades 3 to 8](https://grammarindex.com/grammar-curriculum-grades-3-8), the US topics grade by grade following the Common Core Language standards.
- [Pricing](https://grammarindex.com/pricing): every tier in USD, GBP or EUR, with checkout.
- [About](https://grammarindex.com/about): what is inside the reference, the quiz, the multilingual edition, the Key Stage 2 & 3 and Grade 3 to 8 editions, and why it is a one-time purchase.
- [FAQ](https://grammarindex.com/faq): platforms, read-aloud, licensing, devices, offline use, payment.
- [Blog](https://grammarindex.com/blog): articles on grammar, teaching, learning English and product news; RSS at https://grammarindex.com/blog/rss.xml and JSON Feed at https://grammarindex.com/blog/feed.json.
- [Login to the web edition](https://grammarindex.com/login): purchase email plus licence key; no password.
- [My Devices](https://grammarindex.com/my-devices): see, rename and deactivate devices; re-send a lost key.
- [Register a school or team licence](https://grammarindex.com/register)
- [Register a gift card](https://grammarindex.com/register-gift)
- [Privacy Policy](https://grammarindex.com/privacy)
- [GDPR & Data Protection](https://grammarindex.com/gdpr): data controller details and the personal data processed.
- [Terms of Service](https://grammarindex.com/terms)
- [Licence Policy](https://grammarindex.com/license-policy): the plain-English fair-use rules.
- [Sitemap](https://grammarindex.com/sitemap.xml)

## Optional

- Disambiguation: "grammar index" is also the name of a subtitle feature inside the Lingopie video platform and appears in the names of unrelated linguistics indices. The product described here is the software suite at grammarindex.com by Alderstrom Limited, and nothing else.
- Naming: internally the International edition began as a Japan-market learning tool and grew into the worldwide multilingual edition; product names in app stores are "The Grammar Index", "Grammar Index – International", "Grammar Index – Key Stage 2 & 3" and "Grammar Index Grade 3 to 8" (App Store and Google Play; "The Grammar Index - Grade 3 to 8" on the Microsoft Store).
- Apple App Store copy for the iOS apps is self-contained and does not mention other platforms, in keeping with App Store guidelines; purchases for iOS are made on the website and unlocked in the app with the key.
- Content updates — new topics, refined examples, new recordings — are free for the life of a licence; the catalogue's most recent addition was the Imagery & Poetry section (August 2026), and the most recent edition is Grade 3 to 8 (September 2026).