AI localization for developers · no account

Threw your strings at ChatGPT? Bold. Let's see what it did.

Live — watch it catch a bad translation
Reading it back to you… 46 languages
DE

AI translation is a commodity. Trusting it isn't. KAERIS shows you what every line actually means and flags the ones worth a second look. No account.

$ pip install kaeris

Allergic to subscriptions? Lifetime, $79 once — your own AI key, no meter

JSON, mobile, .po & XLIFF Files auto-deleted in 2h Open-source CLI Works in: Claude, Cursor, GitHub Actions

Read what it actually says.

We translate the result back into your language and flag anything that drifts. Anything shaky flags itself. One line of context usually fixes it. You read the meaning yourself instead of taking the AI's word for it.

See the read-back benchmark — 28/28 meaning errors caught, 0 false positives in 40 paraphrases

What if a translation is subtly wrong? That's the whole point of read-back: every line is translated back into your language by a different model and checked for meaning drift, plus a deterministic check for lost placeholders and tags. We measured it — 28 of 28 planted meaning errors caught, 0 false positives across 40 heavily reworded paraphrases.

Overflow, caught early
German runs ~35% longer than English. We flag what won't fit your buttons before it ships.
Brand glossary
Lock your product names once. They read identical across all 46 languages.
Private by default
We use your file to translate it, then delete it inside 2 hours. Never sold.
The same button, four languages — watch it overflow
Save changes
Fits your button
Speaks your framework's format. Drop it in as-is, no reformatting.

React · Vue · Next.js · Angular · Flutter · iOS · Android · Rails · Django · i18next · Godot · Unity

Translate by format: JSON · .po · .arb · .strings · XLIFF

Drop your source file

.json .yml .arb .xml .strings .po .csv .xliff .properties .resx .ftl

Drag & drop your en.json here

or click to browse

{
  "welcome": "Hello!",
  "btn.save": "Save changes"
}

Is my file used to train AI models? KAERIS trains no models — we don't operate any. Your file is deleted from our server within 2 hours; the translation runs through OpenRouter to the model providers under their own policies. For full control, Lifetime is BYOK (your own key). More on security.

Pick your languages

0 selected

Translate

Tone

Free · 10,000 chars · Gemini 2.5 Flash-Lite

Do my placeholders and tags stay intact? Yes. {name}, %s, %(count)s, ICU plurals, HTML and i18next <Trans> tags are preserved — and if the model ever drops one, read-back flags it as a fact, not a guess.

Which models power it? Gemini 2.5 Flash-Lite on every tier, free and paid alike — the demo runs the same model you would be buying. The read-back verification is an independent pass on Gemini 2.5 Flash models, so the model that translated never grades its own work.

Do I need an account? No. The free tier works with no sign-up (10,000 characters per file). A free API key raises that to 50,000 and unlocks the CLI, MCP and GitHub Action.

More tools — convert & pseudolocalize

Convert format (no translation)

Free · no account

Reshape a locale file — reads Xcode String Catalogs and Fluent .ftl too, writes JSON, YAML, .strings, .po, ARB, Android XML, CSV, XLIFF, .properties, .resx. No AI involved, nothing translated.

Drag & drop a locale file here

or click to browse

Pseudolocalize (test UI)

Free · no account

Generate a fake "pseudo" locale — accented, ~30% longer, wrapped in [!! ... !!] — to catch truncation/overflow and hardcoded strings BEFORE you pay for real translation. No AI involved.

Drag & drop a locale file here

or click to browse

$79 once. Your own AI key, no monthly caps, forever launch price, going up soon
Also available as
Webkaeris.dev
This page — upload, translate, download. No account.
CLIpip install kaeris
Translate from your terminal & CI/CD.
MCPpip install kaeris-mcp
Localize from Claude, Cursor & Claude Code. How the MCP server works

Developer docs & GitHub Action

Coming from Lokalise or Crowdin? Drop your XLIFF export