Open-Source DeepL Alternative (2026, Free)
Identifying DeepL · Mark source
This hub lists open machine-translation projects people compare with DeepL-class hosted translation products. DeepL is named only to identify that product class. We copy licenses and GitHub star counts from official repositories. We do not rank translation quality against DeepL. Hy-SimulMT and Hibiki-Zero are simultaneous speech MT, not DeepL text API clones.
- LibreTranslate — Self-hosted AGPL machine-translation API powered by Argos Translate.
- Hy-SimulMT — Tencent Hunyuan open-source simultaneous speech MT (30B-A3B). Bidirectional Chinese–English.
- Hibiki-Zero — Kyutai 3B streaming speech-to-speech (fr/es/pt/de→en). Weights CC-BY-NC-SA-4.0.
How we pick
- Active GitHub repository we could open (README or API).
- License copied from that repository.
- Self-hostable translation without a proprietary MT backend.
- No unsourced "beats DeepL" claims.
Comparison
| Name | License | Price | Platforms | Runs locally | Key strengths |
|---|---|---|---|---|---|
| LibreTranslate | AGPL-3.0 | free | Linux, macOS, Windows, Docker | Yes | Self-hosted AGPL machine-translation API powered by Argos Translate. |
| Hy-SimulMT | Apache-2.0 | free | See model card | Yes | Tencent Hunyuan open-source simultaneous speech MT (30B-A3B). Bidirectional Chinese–English. |
| Hibiki-Zero | CC-BY-NC-SA-4.0 | free | See model card | Yes | Kyutai 3B streaming speech-to-speech (fr/es/pt/de→en). Weights CC-BY-NC-SA-4.0. |
Listed tool: LibreTranslate. Listed models: Hy-SimulMT (Tencent Hunyuan Apache-2.0 30B-A3B simultaneous Chinese–English speech MT; compare vs Granite Speech 5.0) and Hibiki-Zero (Kyutai 3B streaming S2ST, fr/es/pt/de→en; weights CC-BY-NC-SA-4.0; compare vs Hy-SimulMT). Argos Translate is documented in the snapshot table below without its own URL yet. Related writing/office pages: Microsoft Word alternatives and Grammarly alternatives. Live-speech (not text MT) also hangs off Otter.ai alternatives.
Sourced snapshot (2026-10-18)
| Field | LibreTranslate | Argos Translate |
|---|---|---|
| Repository | github.com/LibreTranslate/LibreTranslate | github.com/argosopentech/argos-translate |
| Stars / forks | 17,108 / 1,782 | 6,571 / 501 |
| License | AGPL-3.0 | MIT (GitHub field); README also says dual MIT or CC0 |
| Created | 2020-12-19 | 2020-04-07 |
| Last push | 2026-10-12T16:51:33Z | 2026-08-08T12:09:57Z |
| Type | REST API + web UI | Python library + CLI + GUI |
| Engine | Argos Translate / CTranslate2 (README) | OpenNMT / CTranslate2 (README) |
| Quality vs DeepL | Not independently tested | Not independently tested |
Why a translation API is on a DeepL hub
DeepL sells hosted translation. Searchers still type “open source DeepL alternative” when they want offline or self-hosted MT. The API we could fully source on 2026-10-18 is LibreTranslate. The library underneath is Argos Translate.
DeepL is named only to identify the search. We did not copy DeepL pricing into a quality table.
LibreTranslate versus Argos Translate
Use LibreTranslate when you want a Docker/API server and a browser UI. Use Argos Translate when you want to import a Python library or run a desktop GUI without a translation HTTP service. LibreTranslate is an Argos Translate consumer; it is not a second engine.
What we left out
Helsinki-NLP / MarianMT, Meta NLLB, OpenNMT-py, and Bergamot (Firefox Translations) are commonly discussed. They are not in this sourced set yet. We also did not attach every LibreTranslate language pair; that list should come from a live /languages response (see open todos).
Hy-SimulMT and Hibiki-Zero are on this hub because searchers type “open translation” when they want self-hosted MT. Both are streaming speech-to-speech, not DeepL-class text APIs. Hy-SimulMT is Chinese–English. Hibiki-Zero is French / Spanish / Portuguese / German into English. File ASR/AST is Granite Speech 5.0 and Nemotron 3.5 Transcribe — Nemotron 3.5 Transcribe vs Granite Speech 5.0.
See also LibreTranslate, Hy-SimulMT, Hibiki-Zero, Writing & Office, and Microsoft Word alternatives.
Listed options
LibreTranslate
Self-hosted AGPL machine-translation API powered by Argos Translate.
Hy-SimulMT
Tencent Hunyuan open-source simultaneous speech MT (30B-A3B). Bidirectional Chinese–English.
Hibiki-Zero
Kyutai 3B streaming speech-to-speech (fr/es/pt/de→en). Weights CC-BY-NC-SA-4.0.
FAQ
Is there a free open-source DeepL alternative I can self-host?
LibreTranslate is AGPL-3.0 with 17,108 GitHub stars (created 2020-12-19, last push 2026-10-12 in the 2026-10-18 check): a REST API and web UI powered by Argos Translate. Argos Translate itself is MIT (or CC0) with 6,571 stars (last push 2026-08-08): a Python library, CLI, and GUI. "Self-host" means the code is downloadable; models still need disk and RAM. We have not scored language pairs against DeepL.
Does it match DeepL quality?
We have no sourced bake-off against DeepL. Coverage and quality vary by language pair. LibreTranslate pivots through intermediate languages for some pairs, which the Argos Translate README says can cost quality.
What is the license?
AGPL-3.0 on LibreTranslate/LibreTranslate (LICENSE, 2026-10-18). Argos Translate is dual MIT or CC0 per its README. AGPL has network-copyleft conditions. Not legal advice.
Can I use them commercially?
MIT/CC0 (Argos Translate) is permissive. AGPL-3.0 (LibreTranslate) allows commercial use but requires offering corresponding source if you provide the software as a network service. Hy-SimulMT is Apache-2.0 on the card and LICENSE-Hy-SimulMT.txt. Hibiki-Zero weights are CC BY-NC-SA 4.0 on the card README (inference code MIT). Not legal advice.
Is Hy-SimulMT a DeepL clone?
No. Hy-SimulMT is Tencent Hunyuan’s 30B-A3B simultaneous speech-to-speech checkpoint (Apache-2.0, 18 HF likes / 45 GitHub stars, 2026-10-27). Card prose is bidirectional Chinese–English live translation. It is not a hosted text MT API. Compare Hy-SimulMT vs Granite Speech 5.0 for the file-ASR split, or Hibiki-Zero vs Hy-SimulMT for the other streaming S2ST pair.
What is Hibiki-Zero?
Kyutai’s ungated 3B streaming speech-to-speech card (59 likes / 278 GitHub stars, 2026-10-27). Card prose is French, Spanish, Portuguese, and German into English. Weights README says CC BY-NC-SA 4.0; the inference repo is MIT. Not a DeepL text API.
Sources & verification
- https://github.com/LibreTranslate/LibreTranslate
- https://github.com/argosopentech/argos-translate
- https://libretranslate.com
- https://www.argosopentech.com
- https://www.deepl.com/
- https://huggingface.co/tencent/Hy-SimulMT-30B-A3B
- https://github.com/Tencent-Hunyuan/Hy-SimulMT
- https://huggingface.co/kyutai/hibiki-zero-3b-pytorch-bf16
- https://github.com/kyutai-labs/hibiki-zero
License notes are not legal advice. Read the original LICENSE. Trademark & disclaimer.