Learn faster!

▶ Try it: https://verttigo28.github.io/Learn-Faster/ — click "Install" on a starter pack and start reviewing.

An offline-first app to learn a language (built for Indonesian, works for any language) with flashcards, spaced repetition, quizzes and sentence exercises. Everything is stored locally in the browser / on the device (IndexedDB) — no account, no server.

Available as a web app (PWA, works offline) and an Android app (Capacitor). The interface is in English and French, and new languages are easy to add (see Translating the app).

Features

• Vocabulary decks with tags, editable in the app
• Spaced repetition (SM-2): daily review across all decks, 4 answer levels (Again / Hard / Good / Easy) with the next interval shown, reverse direction (translation → term), configurable new cards per day
• Exercises: multiple choice, typed answers (tolerant to case, accents, listed alternatives and one typo), word order, cloze (fill in the blank), dictation (text-to-speech), match game (pair words with their meaning against the clock), and retry mistakes at the end of any session
• Quizzes (QCM) with explanations and an optional timer
• Session generator by tags, level (A1 / A2 / B1) and sources, with tag search and a live count of matching items
• Stats: streak and best streak, 20-week activity calendar, 30-day chart, per-deck progress (new / learning / mastered), hardest words, full history with per-question corrections and PDF export
• Import / export: JSON (single deck or full backup including SRS progress), CSV / TSV (Anki "Notes in Plain Text", Quizlet, spreadsheets), from a file, a URL or pasted text
• Starter packs: one click installs a complete Indonesian course (see below)
• Deck library with search, progress bars and due counts; global search; daily goal; backup reminder; light / dark / system theme; keyboard shortcuts (? shows them)

Starter packs

public/packs/ ships ready-to-use Indonesian content, installable from the home page:

Pack	Vocabulary	Grammar quizzes	Sentences
Indonesian for English speakers (indonesian-en)	34 themed decks, ~1,700 words (A1 → B1)	18 exams, ~390 questions with explanations	20 decks, ~540 everyday sentences
Indonésien pour francophones (indonesian-fr)	same content with French definitions	same, explained in French	same, French translations

A pack is a folder with a pack.json and vocab/, qcm/, phrases/ sub-folders containing regular import files (formats below). After adding or editing files run npm run packs to rebuild public/packs/index.json; npm test validates every pack file with the app's import validator.

Getting started

Requirements: Node.js (LTS) and npm.

npm install
npm run dev          # dev server
npm test             # unit / component tests (Vitest + fake-indexeddb)
npm run test:e2e     # end-to-end tests (Playwright, desktop + mobile)
npm run lint         # ESLint
npm run build        # type-check + production build (+ PWA service worker)
npm run packs        # rebuild the starter packs manifest

GitHub Actions runs lint, tests and the build on every push / pull request.

Docker

docker compose up -d --build   # builds the app and serves it with nginx on http://localhost:3000

Android (Capacitor)

npm run build
npx cap sync android   # copies the build and plugins (filesystem, share, status-bar)
npx cap open android

On Android, exports (JSON / PDF) open the system share sheet (save to Files, Drive, e-mail…).

Pronunciation (offline, no voice to install)

Words are spoken from the best available source:

1. Recorded audio for every Indonesian word and sentence of the starter packs (public/audio/id/, ~2,200 small MP3s). Instant and offline, same voice on every device.
2. A device voice for the language, when one is installed.
3. An in-browser neural voice (Piper, via onnxruntime-web) for your own words: downloaded automatically once (~80 MB) and cached for offline use. Nothing for the learner to install.

Regenerate the recordings after editing the packs with npm run audio (only missing files; -- --force for all). It runs Piper in headless Chromium (Playwright) and encodes 32 kbps MP3.

License: the Indonesian voice is trained on data licensed CC BY-NC-SA 4.0, so the recordings are non-commercial only — see public/audio/id/LICENSE.md.

Import formats

Supported JSON types: vocab_deck, qcm_exam, sentence_deck, revisions_bundle (full backup). Invalid files are rejected with precise error paths (e.g. items[3].term) and nothing is imported.

{ "type": "vocab_deck", "id": "id-food", "title": "Food", "from": "id", "to": "en",
  "items": [{ "id": "1", "term": "makan", "definition": "to eat", "tags": ["verb", "a1"] }] }

{ "type": "qcm_exam", "id": "negation", "title": "Negation", "durationSeconds": 600,
  "questions": [{ "id": "1", "prompt": "Negate a verb?", "explanation": "tidak + verb",
    "choices": [{ "id": "a", "text": "tidak", "correct": true }, { "id": "b", "text": "bukan", "correct": false }] }] }

{ "type": "sentence_deck", "id": "restaurant", "title": "At the restaurant",
  "items": [{ "id": "1", "text": "Saya mau makan nasi goreng.", "translation": "I want to eat fried rice." }] }

Definitions may list alternatives accepted in typed answers: "eat / have a meal". Re-importing a deck with the same id replaces its content and keeps spaced-repetition progress for items that still exist.

CSV / TSV (vocab): columns term, definition, optional tags (space, | or , separated); the separator is detected automatically, a header row and Anki # directives are skipped.

Keyboard shortcuts

• Everywhere: ? help, g h home, g r today's review, g s search
• Flashcards: Space flip, 1–4 grade
• Quizzes: 1–9 answer, ← / → navigate
• Generated sessions: Enter check / next, 1–9 pick an answer

Translating the app

UI strings live in src/i18n/locales/<code>/ (one file per area: home.ts, stats.ts…). English is the source of truth and every other language is type-checked against it, so a missing key fails npm run build.

To add a language:

1. Copy src/i18n/locales/en to src/i18n/locales/<code> (e.g. id, es).
2. Translate the strings. Keep the keys and {placeholders}; "one | other" are plural forms.
3. Register it in src/i18n/locales/index.ts (name is how the language calls itself).

In code: $t("home.title") in templates, t("stats.entries", { count }) in scripts (import { t } from "../i18n"). The language is detected from the device and can be changed in Settings.

Project structure

src/
  db/          Dexie schema and migrations (IndexedDB)
  services/    import/export, validation, spaced repetition, practice engine, stats, PDF, packs…
  pages/       one Vue component per route
  components/  shared UI (modal, dialogs, chart, word-order exercise)
  i18n/        translations
public/packs/  starter content
tests/         Vitest unit and component tests
e2e/           Playwright end-to-end tests

Notes

• Data is local: clearing the browser storage deletes it. Export regularly (the home page reminds you after 7 days).
• PDF export uses standard fonts (Latin characters only).