# Linguin

> Multilingual dictionary, translation and language practice in 120+ languages. Meanings, slang, pronunciation and examples on the web, and the same engine as a public API.

Linguin is the multilingual dictionary that tells you what words actually mean, in 120+
languages, and lets you practice using them in real conversation. Every lookup returns a
definition with examples, synonyms, etymology, usage notes, common mistakes and an FAQ.
The same engine translates and localizes text through a public API.

Guiding idea: *words have no translations, they have meanings.* Linguin explains what a
word means in context rather than swapping it for the nearest equivalent.

## Dictionary URLs

- `/{term}` - English entry (e.g. `/serendipity`, `/rizz`). Case sensitive, so `/NASA` and `/nasa` are different entries.
- `/{lang}/{term}` - entry in that language, written in its own script (e.g. `/pt/saudade`, `/ru/слово`, `/ja/木漏れ日`).
- `/{lang}-{lang}/{term}` - cross-language entry, source to target (e.g. `/fr-en/bonjour`, `/es-en/habibi`).

Language codes are ISO 639-1. Older Latin-transliterated paths for non-Latin entries 301
to the native-script URL.

## Pages

- [Home](https://linguin.xyz/): live feed of the dictionary, recently reviewed and trending entries.
- [About](https://linguin.xyz/@about): what Linguin is and who builds it.
- [Exercises](https://linguin.xyz/@exercises): vocabulary practice, open to guests and signed-in users. Multiple choice, either pick the meaning of a term or the term for a meaning.
- [Talk](https://linguin.xyz/@talk): AI conversation practice with feedback on what you said.
- [Articles](https://linguin.xyz/@articles): editorial posts on language, learning and usage.
- [Updates](https://linguin.xyz/@news): product and API release notes.
- [Pricing](https://linguin.xyz/@pricing): learner subscription plans.
- [Sitemap](https://linguin.xyz/sitemap.xml): every published entry and page.

## API

Base URL `https://api.linguin.xyz`. Every method is its own path and takes a POST with a
JSON body, a bearer key and an `API-Version` header. Calls answer inline by default, or
return a `req_id` immediately and POST the result to a `webhook` if one is passed.

```
POST https://api.linguin.xyz/lookup
Authorization: Bearer YOUR_API_KEY
API-Version: 2026-06-01
Content-Type: application/json

{ "text": "bonjour", "lang": "fr", "locale": "en", "mode": "fast" }
```

Keys are per account: a sandbox key for evaluation, a live key on a paid plan. Billing is
prepaid, deducted the moment a result is delivered, and every response carries a `billed`
object with the exact charge.

### Methods

- `POST /lookup` - the dictionary entry for a term. `mode: "fast"` returns just the definition, `deep` the complete entry.
- `POST /reverse` - describe a meaning, get the words that fit. `mode: "terms"` returns bare terms, `fast` or `deep` expands each match to a full entry.
- `POST /translate` - translate text. `deep` resolves idiom, register and tone. `live: true` checks the wording against current real-world usage, `humanizer: true` rewrites it to read as human writing.
- `POST /localize` - bulk translation of a string array for UI and app strings, returned aligned one to one, up to 1000 strings per call.
- `POST /get` - fetch the result of an earlier call by `req_id`, the recovery path for a missed webhook. Free.
- `POST /balance` - current prepaid balance in USD. Free.
- `POST /topup` - add funds, $25 minimum, returns a Stripe payment link. Free.
- `POST /refund` - send unused balance back to the card. Free.
- `POST /report` - usage breakdown. Free.
- `POST /key` and `POST /revoke` - manage bearer keys. Free.

### Rates

Dictionary bills per call or per match, translation bills per source word not for punctuation or white space. There are no
base or per-call fees on translation.

- lookup fast `$0.003` / call, lookup deep `$0.005` / call
- reverse terms `$0.002` / call, reverse fast `$0.004` / match, reverse deep `$0.006` / match
- translate fast `$0.05` / 1K words, translate deep `$0.20` / 1K words
- `live` and `humanizer` each bill the words once more at the tier's rate
- translation requests bill a 30-word minimum, once per call, not per string

### API pages

- [API](https://linguin.xyz/@api): what the API does and who it is for.
- [API docs](https://linguin.xyz/@api/docs): full reference, with sections for [lookup and reverse](https://linguin.xyz/@api/docs#dictionary), [translate](https://linguin.xyz/@api/docs#translate), [localize](https://linguin.xyz/@api/docs#localize), [delivery](https://linguin.xyz/@api/docs#delivery), [errors](https://linguin.xyz/@api/docs#errors) and [billing](https://linguin.xyz/@api/docs#billing).
- [API pricing](https://linguin.xyz/@api/pricing): the rate card and how to get a key.

### SDKs

- [linguin-api on PyPI](https://pypi.org/project/linguin-api/): official Python client.
- [linguin-api on npm](https://www.npmjs.com/package/linguin-api): official JavaScript and TypeScript client.

## Legal

- [Terms](https://linguin.xyz/@legal/terms)
- [Privacy](https://linguin.xyz/@legal/privacy)
- [API Terms](https://linguin.xyz/@legal/api-terms)
- [Data Processing Addendum](https://linguin.xyz/@legal/dpa)
- [Refunds](https://linguin.xyz/@legal/refunds)

## About

- Built by Surfy Ltd, registered in England and Wales, No. 15026168. Founder: Alexander Yermolenko.
- Tagline: "Words have no translations. They have meanings."