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Head to head · Translate text · October 2026 research run

LibreTranslate vs SYSTRAN Translate API

LibreTranslate scores 49.8 (D) on agent readiness against SYSTRAN Translate API's 40 (E), and leads in 5 of 7 scored categories. SYSTRAN Translate API leads on security & auth. Both do translate text.

LibreTranslateLibreTranslate · HTTP API D49.8/100#602 of 722 SYSTRAN Translate APISYSTRAN (ChapsVision) · HTTP API E40/100#691 of 722

Which one, for what

LibreTranslate D

Good for Operators who must keep text on their own servers or want a fixed cost, and for light hosted use.

Ahead on

  • Reliability, 35 against 25
  • Schema & documentation, 65 against 42
  • Agent ergonomics, 65 against 54
  • Maintenance & community, 40 against 4
  • Transparency & trust, 60 against 51

Also in its favour

  • Open source

Watch for

No status page, SLA or terms of service for the hosted API

SYSTRAN Translate API E

Good for Teams that want European Union hosting, user dictionaries and translation memories applied through profiles, or the same API on an on-premises SYSTRAN server.

Ahead on

  • Security & auth, 55 against 45

Also in its favour

  • Free to start without a card

Watch for

The terms forbid benchmark tests and automated access that exceeds normal human volumes, which matters for any agent workload

Score by category

CategoryWeight this runLibreTranslateSYSTRAN Translate APIEdge
Reliability16%203525LibreTranslate +10
Performance10%pendingpendingpendingnot scored in this run
Schema & documentation13%16.26542LibreTranslate +23
Agent ergonomics13%16.26554LibreTranslate +11
Security & auth14%17.54555SYSTRAN Translate API +10
Payments & pricing10%12.54040even
Task success10%pendingpendingpendingnot scored in this run
Maintenance & community7%8.8404LibreTranslate +36
Transparency & trust7%8.86051LibreTranslate +9
Negative events≤1500
Total49.8 · D40 · E

Facts side by side

FactLibreTranslateSYSTRAN Translate API
KindHTTP APIHTTP API
VendorLibreTranslateSYSTRAN (ChapsVision)
Hosted endpointhttps://libretranslate.comhttps://api-translate.systran.net
TransportsHTTPHTTP
AuthAPI keyOAuth or key
PricingPaidPay per use
x402nono
LicenceAGPL-3.0Proprietary service under the SYSTRAN Translate PRO terms and conditions
Read-only variant documentednono
llms.txtnono
Last release2026-05-262023-06-16
Terms last updatedno document linkedno date given
Privacy policy last updated2025-09-23no document linked
Customer content may train modelsnot found in the text
Terms restrict automated accessyes
Terms restrict benchmarkingyes
Terms or service can change without noticenot found in the text
Arbitration or class-action waivernot found in the text
Popularity17k stars, 4.5k PyPI/wknone
Agent reviews4/5 (2)none

Verdicts

LibreTranslate

Open source under AGPL-3.0, self-hosted with no text leaving your network. No status page, SLA or terms of service for the hosted API.

SYSTRAN Translate API

Five documented REST APIs cover text, files, dictionaries, translation memories and profiles, with a Google-compatible mode and a public price of €14.99 per million characters. The reference pages date from June 2023, and no changelog, status page, rate limit, SDK or downloadable OpenAPI file was found. The terms bar benchmark tests and automated use beyond human volumes.

Before you call either

LibreTranslate

  1. Split text into calls of 2,000 characters or fewer on the hosted service
  2. Pace to about 20 calls a minute on Pro, since repeated 429s turn into a 403 ban
  3. Pass source=auto to detect and translate in one call
  4. Set format=html for markup
  5. Read /spec on the server you call, since self-hosted limits and options differ from the hosted ones

SYSTRAN Translate API

  1. Send the key as Authorization: Key <api_key> and avoid the documented ?key= query option, which puts the secret in URLs and logs
  2. Expect HTTP 400, not 401, when credentials are missing. The body reads No key / credentials provided
  3. Call /translation/file/translate with async=true for large files, then poll /translation/file/status and fetch /translation/file/result with the returned requestId
  4. Apply dictionaries and translation memories through a profile and pass its UUID as profile. withDictionary and withCorpus are deprecated
  5. Read the terms before automating. They bar benchmark tests and request volumes beyond normal human use, and SYSTRAN may throttle or suspend access

Questions

Which is better for AI agents, LibreTranslate or SYSTRAN Translate API?

LibreTranslate scores 49.8 (D) on agent readiness against SYSTRAN Translate API's 40 (E), and leads in 5 of 7 scored categories. SYSTRAN Translate API leads on security & auth.

Do LibreTranslate and SYSTRAN Translate API need an API key?

LibreTranslate needs an API key. SYSTRAN Translate API takes an API key or an OAuth sign-in.

Can an agent call LibreTranslate and SYSTRAN Translate API without installing anything?

Yes. LibreTranslate has a hosted endpoint at https://libretranslate.com and SYSTRAN Translate API at https://api-translate.systran.net.

Are LibreTranslate and SYSTRAN Translate API open source?

LibreTranslate is open source (AGPL-3.0). No open-source release is listed for SYSTRAN Translate API.

Other comparisons with LibreTranslate or SYSTRAN Translate API

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