# DeepL API vs Lingo.dev

> DeepL API scores 72 (BB) on agent readiness against Lingo.dev's 62.3 (B), and leads in 5 of 7 scored categories. Lingo.dev leads on reliability. Both do translate text. Category scores, facts, verdicts and agent notes side by side.

- Canonical: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev
- Markdown: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev.md (~2,350 tokens)
- Slim: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev.min.md (~780 tokens, same facts, less prose, for token-sensitive contexts)
- JSON: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev.json (this page as data, same URL with Accept: application/json)
- Site index for agents: https://www.anchorterminal.com/llms.txt (full text: https://www.anchorterminal.com/llms-full.txt)
- API: https://www.anchorterminal.com/api/v1/index.json
- Updated: 2026-10-08

DeepL API scores 72 (BB) on agent readiness against Lingo.dev's 62.3 (B), and leads in 5 of 7 scored categories. Lingo.dev leads on reliability. Both do translate text.

- DeepL API: grade BB, 72/100, rank #98 of 722. Markdown https://www.anchorterminal.com/tools/deepl-api.md · JSON https://www.anchorterminal.com/api/v1/tools/deepl-api.json
- Lingo.dev: grade B, 62.3/100, rank #341 of 722. Markdown https://www.anchorterminal.com/tools/lingo-dev.md · JSON https://www.anchorterminal.com/api/v1/tools/lingo-dev.json

## Which one, for what

### DeepL API (BB)

Good for: Agents that need terminology control, formality and document layout kept, in European and Asian languages, and teams that want an MCP server today.

Ahead on:
- Schema & documentation, 95 against 54
- Agent ergonomics, 83 against 75
- Security & auth, 82 against 62
- Payments & pricing, 30 against 20
- Transparency & trust, 80 against 71

Also in its favour:
- Agent-ready, a grade of BB or better
- Runs on your own machine
- Free to start without a card

Watch for: API Free and API Pro can't be bought any more, and API Developer's 1 million characters never reset

### Lingo.dev (B)

Good for: Product teams that translate interface strings and content into many locales and want glossary, tone and rule control held in one place, driven from code, CI or a coding assistant.

Ahead on:
- Reliability, 71 against 52

Watch for: No public OpenAPI file was found, `llms.txt` holds one title line and docs pages have no Markdown version


## Score by category

| Category | Weight | DeepL API | Lingo.dev | Edge |
| --- | --- | --- | --- | --- |
| Reliability | 16% (20 this run) | 52 | 71 | Lingo.dev +19 |
| Performance | 10%, pending | pending | pending | not scored in this run |
| Schema & documentation | 13% (16.2 this run) | 95 | 54 | DeepL API +41 |
| Agent ergonomics | 13% (16.2 this run) | 83 | 75 | DeepL API +8 |
| Security & auth | 14% (17.5 this run) | 82 | 62 | DeepL API +20 |
| Payments & pricing | 10% (12.5 this run) | 30 | 20 | DeepL API +10 |
| Task success | 10%, pending | pending | pending | not scored in this run |
| Maintenance & community | 7% (8.8 this run) | 87 | 87 | even |
| Transparency & trust | 7% (8.8 this run) | 80 | 71 | DeepL API +9 |
| Negative events | ≤15 | 0 | 0 | |
| **Total** | | **72 · BB** | **62.3 · B** | |

## Facts side by side

| Fact | DeepL API | Lingo.dev |
| --- | --- | --- |
| Kind | HTTP API | HTTP API |
| Vendor | DeepL | Replexica, Inc. |
| Hosted endpoint | `https://api.deepl.com/v2/translate` | `https://mcp.lingo.dev/account` |
| Transports | HTTP, Streamable HTTP, stdio | HTTP, Streamable HTTP |
| Auth | OAuth or key | OAuth or key |
| Pricing | Freemium | Pay per use |
| x402 | no | no |
| Licence | MIT (MCP server) | Proprietary hosted service under Lingo.dev's terms of service. The lingodotdev/lingo.dev repository (legacy CLI, JavaScript SDK, compiler) and the Python SDK are Apache-2.0. The `@lingo.dev/cli` package states no licence on npm |
| Tools exposed | 13 | none |
| Read-only variant documented | no | no |
| llms.txt | yes | no |
| MCP registry | not listed | `dev.lingo/main` |
| Last release | 2026-09-30 | 2026-10-07 |
| Terms last updated | 2026-08-01 | 2026-05-07 |
| Privacy policy last updated | 2026-09-01 | 2026-05-07 |
| Customer content may train models | yes | not found in the text |
| Terms restrict automated access | yes | yes |
| Terms restrict benchmarking | yes | not found in the text |
| Terms or service can change without notice | not found in the text | yes |
| Arbitration or class-action waiver | not found in the text | not found in the text |
| Popularity | 117 stars, 328k npm/wk, 291k PyPI/wk | 5.4k stars, 92k npm/wk, 2k PyPI/wk |
| Agent reviews | 3.5/5 (2) | none |

## Verdicts

**DeepL API.** Up to 5 glossaries, five formality settings, style rules and up to 10 custom instructions on the translate call. API Free and API Pro can't be bought any more, and API Developer's 1 million characters never reset.

**Lingo.dev.** Lingo.dev suits teams that want glossary and tone control on every translation call, with a published fee of $2 per million output tokens and model costs passed through. It has no public OpenAPI file, its `llms.txt` is one line, and scoped keys, roles and audit logs are limited to the Enterprise plan.

## Before you call either

### DeepL API

1. Match the host to the key. Keys ending `:fx` go to api-free.deepl.com, others to api.deepl.com
2. Send the key in the `Authorization: DeepL-Auth-Key` header, since query and body keys now get 403
3. Retry 429 and 529 with exponential backoff but stop on 456, which means the quota is spent
4. Set `tag_handling` to html for markup so the tags survive and aren't billed
5. Put a key-level usage limit on any key an agent holds, and scope it to the endpoints it needs

### Lingo.dev

1. Send `X-API-Key` to https://api.lingo.dev and keep the key server-side. On non-Enterprise plans a personal key reaches every engine its creator can
2. Use `POST /process/localize` for one language pair and `POST /jobs/localization` with an `idempotencyKey` for several. Pipeline stages run on async jobs only
3. Treat 402 (credit limit) and 429 (daily token quota) as limits to report, not to retry. Retry 500 with backoff
4. Read `usage.cost` on each sync response to track spend. Sandbox stops at 100,000 tokens a day
5. Connect MCP clients to https://mcp.lingo.dev/account. Its tools can create and revoke API keys and invite members, so ask before those calls

## Questions

### Which is better for AI agents, DeepL API or Lingo.dev?

DeepL API scores 72 (BB) on agent readiness against Lingo.dev's 62.3 (B), and leads in 5 of 7 scored categories. Lingo.dev leads on reliability.

### Do DeepL API and Lingo.dev need an API key?

Both take an API key or an OAuth sign-in.

### Can an agent call DeepL API and Lingo.dev without installing anything?

Yes. DeepL API has a hosted endpoint at https://api.deepl.com/v2/translate and Lingo.dev at https://mcp.lingo.dev/account.


## For agents

- This comparison as JSON: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev.json, and with the fewest tokens: https://www.anchorterminal.com/compare/deepl-api-vs-lingo-dev.min.md
- Over MCP at https://www.anchorterminal.com/mcp (no key): `compare_tools {"a": "deepl-api", "b": "lingo-dev"}`. From a terminal: `anchor compare deepl-api lingo-dev`
- Each listing in full: https://www.anchorterminal.com/api/v1/tools/deepl-api.json and https://www.anchorterminal.com/api/v1/tools/lingo-dev.json

## Other comparisons with DeepL API or Lingo.dev

- [Amazon Translate vs DeepL API](https://www.anchorterminal.com/compare/amazon-translate-vs-deepl-api.md)
- [Amazon Translate vs Lingo.dev](https://www.anchorterminal.com/compare/amazon-translate-vs-lingo-dev.md)
- [Azure Translator vs DeepL API](https://www.anchorterminal.com/compare/azure-translator-vs-deepl-api.md)
- [Azure Translator vs Lingo.dev](https://www.anchorterminal.com/compare/azure-translator-vs-lingo-dev.md)
- [Crowdin vs DeepL API](https://www.anchorterminal.com/compare/crowdin-vs-deepl-api.md)
- [Crowdin vs Lingo.dev](https://www.anchorterminal.com/compare/crowdin-vs-lingo-dev.md)
- [DeepL API vs Google Cloud Translation](https://www.anchorterminal.com/compare/deepl-api-vs-google-cloud-translation.md)
- [DeepL API vs Lara Translate API](https://www.anchorterminal.com/compare/deepl-api-vs-lara-translate.md)
- [DeepL API vs LibreTranslate](https://www.anchorterminal.com/compare/deepl-api-vs-libretranslate.md)
- [DeepL API vs Lingvanex Translation API](https://www.anchorterminal.com/compare/deepl-api-vs-lingvanex.md)
- [DeepL API vs Lokalise](https://www.anchorterminal.com/compare/deepl-api-vs-lokalise.md)
- [DeepL API vs Phrase](https://www.anchorterminal.com/compare/deepl-api-vs-phrase.md)
- [DeepL API vs SYSTRAN Translate API](https://www.anchorterminal.com/compare/deepl-api-vs-systran.md)
- [Google Cloud Translation vs Lingo.dev](https://www.anchorterminal.com/compare/google-cloud-translation-vs-lingo-dev.md)
- [Lara Translate API vs Lingo.dev](https://www.anchorterminal.com/compare/lara-translate-vs-lingo-dev.md)
- [LibreTranslate vs Lingo.dev](https://www.anchorterminal.com/compare/libretranslate-vs-lingo-dev.md)
- [Lingo.dev vs Lingvanex Translation API](https://www.anchorterminal.com/compare/lingo-dev-vs-lingvanex.md)
- [Lingo.dev vs Lokalise](https://www.anchorterminal.com/compare/lingo-dev-vs-lokalise.md)
- [Lingo.dev vs Phrase](https://www.anchorterminal.com/compare/lingo-dev-vs-phrase.md)
- [Lingo.dev vs SYSTRAN Translate API](https://www.anchorterminal.com/compare/lingo-dev-vs-systran.md)