Unbabel

Unbabel is a Language Operations (LangOps) platform that combines always-on AI translation with on-demand human review to localize customer support, marketing, and other business content at scale. Its long-standing developer surface is the Unbabel Translation API (tapi/v2, base https://api.unbabel.com/tapi/v2), an asynchronous REST API where callers submit text with a source/target language pair, tone, and topic, then retrieve the completed AI-plus-human translation by uid or via a callback. Unbabel also offers a pure machine-translation path (mt_translation) and helper resources for language pairs, tones, topics, word count, and account details. Unbabel has since launched the standalone LLM-based product Widn.AI (its own RESTful API at widn.ai) and, following its combination with TransPerfect, its research and models (TowerLLM, COMET, Widn.AI) now also feed the GlobalLink platform; the tapi/v2 Translation API remains the documented developer surface at developers.unbabel.com.

Unbabel publishes 6 API contracts indexed on the APIs.io network, including Account API, Language Pairs API, Machine Translation API, and 3 more. Tagged areas include Translation, Localization, Language Operations, LangOps, and Machine Translation.

The Unbabel catalog on APIs.io includes 1 Spectral governance ruleset.

Unbabel’s developer surface includes authentication, documentation, engineering blog, and 11 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

32.1/100 thin ▬ flat Agent 19/100 agent aware Front door AI 4/6 moderate Heartbeat 0/100 dormant saas Full breakdown ↓
scored 2026-11-13 · rubric v0.28.0 · Show this score on your site →

AccessPaid

1 published contract

Translation LocalizationLanguage OperationsLangOpsMachine Translation Human-in-the-Loop Artificial Intelligence

Kin Score

Kin Score How this is scored →
scored 2026-11-13 · rubric v0.28.0

Composite quality — 32.1/100 · thin

Contract Quality 9.4 / 19

Developer Ergonomics 3.8 / 15

Access Clarity 2.6 / 15

Operational Transparency 2.1 / 10

Contract Governance 1.2 / 9

Discoverability 5.0 / 8

Regulatory Posture 3.1 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 19/100 · agent aware

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 0 / 9

Stable Error Semantics 0 / 8

Request/Response Examples 0 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 0 / 6

Agent Skills 0 / 5

Well-Known Catalog 0 / 4

Consent & Bot Identity 0 / 3

A2A Agent Card 0 / 8

Dry-Run / Simulate Mode 0 / 4

Delegated User Identity 0 / 6

Protected Resource Metadata 0 / 5

Registration Without a Human 0 / 6

Agentic Commerce Well-Known Document 0 / 5

Pagination 0 / 5

Distinct Operations 3 / 3

MCP Tool Quality 6 / 6

Regulatory Posture applies to this provider. Its tags matched the Horizontal (data, software, accessibility, platform) regime, so Regulatory Posture carries 15 points of the composite. If this regime is wrong for your business, say so on your provider repo — the applicability map is public and we will correct it.

Create-or-Update Ergonomics applies to this provider. This API accepts writes, so it carries 10 points of the composite. It is scored from the published contracts themselves: whether a caller can create-or-update in one call, whether the write accepts a key the caller already holds, and whether the response says which branch ran. Without that, every write needs a search-and-branch in front of it, and the first time that check is skipped a duplicate record is created. Scored against the observed mean rather than raw — a provider at the catalog average is unchanged by this facet, not penalised by it.

The six quality facets above are damped to 75 points between them, because the conditional facet above carries the other 25. That is why each facet's contribution is shown against a damped maximum: raising a quality facet moves the composite by 75% of its nominal weight, not 100%. The full arithmetic is at apis.io/rating/.

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Agent readiness — checks not met, largest first (exact, from this profile):

MCP Server +12 pts — deployment.mode + probe verdict on the mcp/ manifest, not the pointer; an unprobed slug falls back to authorship Ask about this →
Idempotency +9 pts — OpenAPI mutating operations declare an idempotency key — a header, a request-body property, or a named de-duplication token whose own description says so (verified); else common[].type matches /idempoten/i (documented) Ask about this →
Stable Error Semantics +8 pts — OpenAPI $refs a shared error schema across 4xx/5xx responses (verified), else common[].type includes ErrorCatalog / ErrorCodes / DeclineCodes Ask about this →
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0 Ask about this →
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link Ask about this →
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document Ask about this →

10 more unmet checks in the Agent Readiness table above.

Kin Score — facets with the most composite points still available (weight × headroom):

Access Clarity scores 17.0 — up to +16.6 composite points Ask about this →
Developer Ergonomics scores 25.0 — up to +15.0 composite points Ask about this →
Contract Quality scores 50.2 — up to +12.5 composite points Ask about this →

Each check links to what satisfies it. Publish the artifact, or tell us where it already lives, and the score moves on the next scoring run.

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Improve this rating by publishing the missing artifacts — every area above can be raised, and the full rubric is at apis.io/rating/. Every facet and dimension name above is a link: it opens that measurement's own page — what it means, the exact checks that feed it, how the whole catalog distributes on it, and the providers at the top of it. This rating is computed from the provider profile at artifacts.apis.io/unbabel/apis.yml: open an issue on github.com/api-evangelist/unbabel to ask a question or point us at an artifact you publish. Submit an artifact on GitHub — free → Manage your own listing — the Influence plan, $499/mo →

Markets this provider is in provisional

The Kin Score Market layer reads a provider inside its market: its position, and how deep its integrations go. Depth is only comparable within a position. Provisional and unweighted: not part of the Kin Score or agent readiness.

Market	Position	Depth	Registered MCP server	Declares compatibility
Localization and Translation Management	builds-on	42.9	-	-
Hugging Face Hub Organisations	builds-on	42.9	-	-

Registered MCP server and declares compatibility are report only — not weighted. Undeclared means we found nothing we can read, so there is no number: we never infer integrations.

Standards implemented 1

Standards this provider implements or carries. De facto ones are profiled and measured by the API Commons; formal ones come from the standards directory and are linked by the provider's own tags. The evidence column says how each claim was established — not that it was made.

OpenAPI

measured — observed by APIs.io (published)

APIs 6

Individual APIs this provider publishes, each with its own machine-readable definition.

Unbabel Account API

Authenticated customer account information.

Unbabel Language Pairs API

Supported source-to-target language combinations.

Unbabel Machine Translation API

Pure machine-translation jobs, optionally upgradeable to human review.

Unbabel Tone and Topic API

Available tones and topics/domains for a translation.

Unbabel Translation API

Submit and manage AI-plus-human translation jobs.

Unbabel Word Count API

Billable word count calculation for a block of text.

Open Collections 7

Open, tool-agnostic API collections (OpenAPI-derived and Bruno).

Unbabel Translation Account API

OPEN COLLECTION

Unbabel Translation Account Language Pairs API

OPEN COLLECTION

Unbabel Translation Account Machine Translation API

OPEN COLLECTION

Unbabel Translation Account Tone and Topic API

OPEN COLLECTION

Unbabel Account Translation API

OPEN COLLECTION

Unbabel Translation Account Word Count API

OPEN COLLECTION

Unbabel Translation API

OPEN COLLECTION

Scroll for all 7

Unbabel API pricing

Not yet checked against Unbabel's own pricing page. Compiled by API Evangelist on 2026-07-03 from unbabel.com/; confirm before you rely on a figure.

Plan	Price
Pay As You Go usage	—
Subscription / Committed Volume subscription	—
Enterprise enterprise	—

Plan details, limits and sources →

Rate limits

Translation API Requests: not published requests
Translation Volume: per contract words
Job Status Polling: not published requests

Compiled by API Evangelist, not yet checked against Unbabel's documentation. Rate-limit details →

Pricing Plans 1

Published pricing tiers and plan structures.

Unbabel Plans Pricing

3 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Unbabel Rate Limits

3 limits

RATE LIMITS

Compliance 1

Attestations the provider states (SOC 2, ISO 27001 and others), quoted from its own trust page. APIs.io verifies none of them.

Unbabel

3 quoted statements, read from Unbabel's own page on 2026-11-10.

COMPLIANCE

FinOps 1

Cost, billing, and metering signals for API financial operations.

Unbabel Finops

FINOPS

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs. Counts are the severity each rule declares, not results of running them.

Unbabel API Rules

64 rules · 61 error-severity 2 warn-severity 1 info-severity

SPECTRAL

Security Posture 4

Authentication, domain security, vulnerability disclosure, and trust-center signals.

Unbabel Authentication

apiKey · 1 scheme

SECURITY

Unbabel Domain Security

TLSv1.3 · HSTS · DNSSEC · DMARC

SECURITY

Unbabel Vulnerability Disclosure

no policy recorded

SECURITY

Unbabel Trust Center

ISO 27001, GDPR

SECURITY

Agentic Access (API Evangelist recommendations) 1

Recommended x-agentic-access execution contracts for AI agents.

Unbabel Agentic Access

13 operations · 4 acting

AGENTIC

Resources

Documentation 1

Reference material describing how the API behaves

Documentation

Documentation

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 4

Authentication, authorization, and security posture

TrustCenter

TrustCenter

VulnerabilityDisclosure

VulnerabilityDisclosure

DomainSecurity

DomainSecurity

Authentication

Authentication

Operate 1

Status, limits, changes, and where to get help

RateLimits

RateLimits

Commercial 2

Pricing, plans, and the legal terms of use

Plans

Plans

FinOps

FinOps

Company 3

The organization behind the API

LinkedIn

Website

Website

Blog

Blog

Other 1

Properties that don't map to a standard resource type

Attestations

Attestations

Source (apis.yml)

aid: unbabel
url: https://raw.githubusercontent.com/api-evangelist/unbabel/refs/heads/main/apis.yml
name: Unbabel
kind: company
description: Unbabel is a Language Operations (LangOps) platform that combines always-on AI translation with on-demand human
  review to localize customer support, marketing, and other business content at scale. Its long-standing developer surface
  is the Unbabel Translation API (tapi/v2, base https://api.unbabel.com/tapi/v2), an asynchronous REST API where callers submit
  text with a source/target language pair, tone, and topic, then retrieve the completed AI-plus-human translation by uid or
  via a callback. Unbabel also offers a pure machine-translation path (mt_translation) and helper resources for language pairs,
  tones, topics, word count, and account details. Unbabel has since launched the standalone LLM-based product Widn.AI (its
  own RESTful API at widn.ai) and, following its combination with TransPerfect, its research and models (TowerLLM, COMET,
  Widn.AI) now also feed the GlobalLink platform; the tapi/v2 Translation API remains the documented developer surface at
  developers.unbabel.com.
deliveryModel:
  model: saas
  open_source: false
  commercial: true
  callable_host: true
  label: Hosted service · you call their endpoint
  confidence: high
  source:
  - openapi
  - pricing
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: paid
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Paid
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-13'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/unbabel.png
x-docs-platform: stoplight
x-docs-platform-confidence: high
x-docs-platform-checked: 2026-10-17
tags:
- Translation
- Localization
- Language Operations
- LangOps
- Machine Translation
- Human-in-the-Loop
- Artificial Intelligence
tags_raw:
- Translation
- Localization
- Language Operations
- LangOps
- Machine Translation
- Human in the Loop
- AI
created: '2026-07-03'
modified: '2026-07-03'
specificationVersion: '0.23'
apis:
- aid: unbabel:unbabel-account-api
  name: Unbabel Account API
  description: Authenticated customer account information.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Account
  properties:
  - type: OpenAPI
    url: openapi/unbabel-account-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
- aid: unbabel:unbabel-language-pairs-api
  name: Unbabel Language Pairs API
  description: Supported source-to-target language combinations.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Language Pairs
  properties:
  - type: OpenAPI
    url: openapi/unbabel-language-pairs-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
- aid: unbabel:unbabel-machine-translation-api
  name: Unbabel Machine Translation API
  description: Pure machine-translation jobs, optionally upgradeable to human review.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Machine Translation
  properties:
  - type: OpenAPI
    url: openapi/unbabel-machine-translation-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
- aid: unbabel:unbabel-tone-and-topic-api
  name: Unbabel Tone and Topic API
  description: Available tones and topics/domains for a translation.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Tone and Topic
  properties:
  - type: OpenAPI
    url: openapi/unbabel-tone-and-topic-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
- aid: unbabel:unbabel-translation-api
  name: Unbabel Translation API
  description: Submit and manage AI-plus-human translation jobs.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Translation
  properties:
  - type: OpenAPI
    url: openapi/unbabel-translation-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
- aid: unbabel:unbabel-word-count-api
  name: Unbabel Word Count API
  description: Billable word count calculation for a block of text.
  humanURL: https://developers.unbabel.com/docs/introduction
  baseURL: https://api.unbabel.com/tapi/v2
  tags:
  - Word Count
  properties:
  - type: OpenAPI
    url: openapi/unbabel-word-count-api-openapi.yml
  - type: Documentation
    url: https://developers.unbabel.com/docs/introduction
  - type: APIReference
    url: https://developers.unbabel.com/reference/translation-list-update
  - type: PostmanCollection
    url: collections/unbabel.postman_collection.json
  - type: OpenCollection
    url: collections/unbabel.opencollection.json
  - type: APIReference
    url: https://developers.unbabel.com/reference/language-pair
  - type: APIReference
    url: https://developers.unbabel.com/reference/tone
  - type: APIReference
    url: https://developers.unbabel.com/reference/word-count
  - type: APIReference
    url: https://developers.unbabel.com/reference/account
common:
- type: AgenticAccess
  url: agentic-access/unbabel-agentic-access.yml
- type: TrustCenter
  url: security/unbabel-trust-center.yml
- type: VulnerabilityDisclosure
  url: security/unbabel-vulnerability-disclosure.yml
- type: DomainSecurity
  url: security/unbabel-domain-security.yml
- type: Authentication
  url: authentication/unbabel-authentication.yml
- type: GitHubOrganization
  url: https://github.com/Unbabel
- type: LinkedIn
  url: https://www.linkedin.com/company/unbabel
- type: Website
  url: https://unbabel.com
- type: Documentation
  url: https://developers.unbabel.com
- type: Plans
  url: plans/unbabel-plans-pricing.yml
- type: RateLimits
  url: rate-limits/unbabel-rate-limits.yml
- type: FinOps
  url: finops/unbabel-finops.yml
- url: https://unbabel.com/feed/
  type: Blog
- type: Attestations
  url: compliance/unbabel-compliance.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

Unbabel API — frequently asked questions

Does Unbabel have an API?

Yes. APIs.io lists 6 APIs from Unbabel, including Unbabel Account API, Unbabel Language Pairs API and Unbabel Machine Translation API, and 3 more.

Is there an OpenAPI specification for the Unbabel API?

Yes. APIs.io indexes 6 OpenAPI specifications for Unbabel, each linked for download from this page.

How do I authenticate with the Unbabel API?

Unbabel uses bearer-token authentication (apiKey · 1 scheme). The details are profiled on APIs.io as Unbabel Authentication.

How much does the Unbabel API cost?

APIs.io lists 3 pricing plans for Unbabel, with each plan's price, limits and inclusions under Pricing on this page.

Is the Unbabel API ready for AI agents?

Unbabel has a Kin Score of 32.1 out of 100 (thin) and an Agent Readiness score of 19.0 (agent-aware), scored by API Evangelist on 2026-11-13.

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