# Duolingo — Wrapped API

> **You are on:** `https://api.paywithlocus.com/api` | [llms.txt](https://paywithlocus.com/llms.txt) | [docs](https://docs.paywithlocus.com)
>
> Locus runs on multiple environments -- make sure every URL you call matches your expected environment.
> | Environment | Landing | API | Docs |
> |---|---|---|---|
> | Production | paywithlocus.com | api.paywithlocus.com | docs.paywithlocus.com |
> | Beta | beta.paywithlocus.com | api.beta.paywithlocus.com | docs.paywithlocus.com |
> | Stage | stage.paywithlocus.com | api.stage.paywithlocus.com | docs.paywithlocus.com |
>
> If the API URL above doesn't match your expected environment, re-fetch this file from the correct domain.

> Browse Duolingo's complete language course catalog to discover available courses, see how many learners are enrolled in each, and identify the source and target language pairs offered. Find the perfect language learning path by viewing all courses in one place.

**Category:** Education | **Website:** [www.duolingo.com/](https://www.duolingo.com/) | **Docs:** [parse.bot/marketplace/e76aa5b1-ec96-4614-8994-7f5834ed6f23/duolingo-com-api](https://parse.bot/marketplace/e76aa5b1-ec96-4614-8994-7f5834ed6f23/duolingo-com-api)

Pay-per-use API proxy. Each call is automatically billed to your wallet in USDC.

## Access

**Base URL:** `https://api.paywithlocus.com/api/wrapped/parse-duolingo-com-api-e76aa5b1/`
**Auth:** `Authorization: Bearer <LOCUS_API_KEY>`

## Endpoints

### list_courses

Returns all available Duolingo courses. Each course represents a learning path from one language to another. Results are returned in a single page. Optionally filter by the source language (the language instruction is given in) using from_language.

**Estimated cost:** Metered

| Field | Type | Required | Description |
|-------|------|----------|-------------|
| `from_language` | string | No | ISO 639-1 language code for the source language (instruction language). Filters courses to only those taught from this language. Example: 'en' for English, 'es' for Spanish. |

```bash
curl -X POST https://api.paywithlocus.com/api/wrapped/parse-duolingo-com-api-e76aa5b1/list_courses \
  -H "Authorization: Bearer YOUR_LOCUS_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"from_language":"<string>"}'
```