Localization QA Platform

Verify translation quality before your users do

QACAT is the QA platform we built for our own localization work — now open to your team. Catch translation issues through deterministic checks, AI analysis, and in-app testing by real linguists, all in one place.

Run it from the UI, your CI, or an AI agent — QACAT exposes a REST API and an MCP server, so an agent can run checks and order human review on its own.

Open QACAT →API & MCP docs →

A platform by Alconost · REST API, MCP and TMS connectors are live

Trusted by global leaders

Four ways to catch issues

Use one, or layer all four — rules where rules are enough, AI where scale matters, humans where judgment counts, and in-context testing before you ship.

AQA

Automated Quality Assurance

Deterministic checks. No AI, no guesswork.

Strict rule-based system — the same result every run
Separates critical Errors from informational Notes, so you fix what matters
Upload a TM and flag every segment that diverges from an exact match

AIQA

AI-driven Quality Assurance

Meaning, tone, and consistency — at volume.

Choose from multiple AI evaluators to fit your content
Fast and scalable across high-volume releases
Honest about its limits — results are triage for humans, not a verdict

LQA

Language Quality Assurance

Certified linguists, scored against a standard.

Human evaluation by professional linguists — not AI
Methodology-based assessment following industry standards
Returns an improvement plan plus a corrected beta translation

LQT

Linguist Quality Testing

Testing in your real UI, not a spreadsheet.

Linguists review strings in the actual product, from your screenshots
AI suggestions first, then human validation
Production-ready LQT report before you ship

Plugs into the tools you already use

Push translations from your CAT, CMS, or pipeline straight into QACAT and pull back structured QA results. Connectors for the big TMSs — and a generic REST API plus MCP for everything else.

TMS / CAT connectorCrowdin, Smartcat

live

REST APIRun reports from CI or your own scripts

live

MCP serverClaude, Cursor, or any AI agent

live

Trados files.sdlxliff · .sdlppx · .sdlrpx

live

Run AQA, AIQA and LQT from your own scripts or CI — no UI needed
Assign linguists from the call: they get the email automatically and validate inside QACAT
Pull back structured results and export as XLSX, HTML, or JSON
Drive the whole thing from an AI agent over MCP — no code required

Create a report — and get linguists assigned

POST https://api.qacat.alconost.com/v1/reports
Authorization: Bearer qct_****

{
  "report_type": "ai_lqa",
  "source_lang": "en",
  "target_langs": ["ru", "de", "ja"],
  "assign_linguists": true
}

# 201 Created
# { "report_id": "rpt_268", "status": "running",
#   "linguists_notified": 3 }

Illustrative — see the API & MCP docs for the current schema.

Read the API & MCP docs →

See the platform for yourself — connect your TMS and run your first checks.

Open QACAT →

Made for everyone who ships in more than one language

Localization agencies

Scale quality control without scaling headcount.

Companies & brands

Control quality at every release, in every language.

Linguists & LocPMs

Spend time on judgment calls, not mechanical checks.

TMS platforms

Add a serious QA layer to your platform via API.

Read our 151 reviews

4.8 (18 Reviews)

4.2 (17 Reviews)

9001:2015
17100:2015
18587-2017

Globalization and Localization Association

American Translators Association

What is QACAT?

QACAT is Alconost's localization QA platform. It catches translation issues three ways — deterministic (rule-based) checks, AI-driven QA (AIQA), and in-app testing by human linguists — in one place, with API/MCP access and Crowdin/Smartcat integration.

Does it replace my linguists?

No — it makes them faster. Deterministic and AI checks clear the mechanical and high-volume issues so your linguists spend their time on the judgment calls that actually need a human.

Which tools does it integrate with?

QACAT connects to Crowdin and Smartcat out of the box, and exposes an API plus an MCP server so you can wire it into CI pipelines or AI-agent workflows.

Can I evaluate machine-translation engines?

Yes. QACAT scores and compares MT engines on your own content and language pairs, so you pick the right engine before committing — not after.

How do I get started?

Open QACAT, connect your TMS, and run your first checks. If you would rather we set up and run the QA workflow for you, request a quote below and a specialist will scope it with you.