Litmus

Email testing and analytics platform that allows developers and marketers to preview, test, and analyze email campaigns across multiple email clients and devices before sending.

Litmus publishes 7 API contracts indexed on the APIs.io network, including Analytics API, Campaigns API, Clients API, and 4 more. Tagged areas include Developer Tools, Email Testing, Marketing Tools, Quality Assurance, and Email.

The Litmus catalog on APIs.io includes 1 JSON-LD context and 1 Spectral governance ruleset.

Litmus’ developer surface includes authentication, documentation, getting-started guide, engineering blog, and 15 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

35.0/100 thin ▬ flat Agent 24/100 agent aware Front door AI 3/6 light Heartbeat 32/100 alive Full breakdown ↓
scored 2026-11-06 · rubric v0.27.0 · Show this score on your site →

AccessEnterprise

4 published contracts

Developer Tools Email TestingMarketing ToolsQuality Assurance Email

What this lets a business do 1

Business capabilities this provider's published APIs can perform, derived from its own contracts. Browse all capabilities →

Marketing Management

BC-400

AnalyticsCampaigns

GET /campaigns POST /campaigns

Kin Score

Kin Score How this is scored →
scored 2026-11-06 · rubric v0.27.0

Composite quality — 35.0/100 · thin

Contract Quality 11.0 / 19

Developer Ergonomics 6.1 / 15

Access Clarity 2.4 / 15

Operational Transparency 1.0 / 10

Contract Governance 0.9 / 9

Discoverability 4.7 / 8

Regulatory Posture 3.2 / 15

Create-or-Update Ergonomics 0.0 / 10

Agent readiness — 24/100 · 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 8 / 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
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)
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0
Request/Response Examples +7 pts — share of operations carrying request/response examples; else an Examples / Code Samples link
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document
Delegated User Identity +6 pts — a served discovery document listing authorization_code in grant_types_supported (served), else an oauth2 authorizationCode flow or openIdConnect declared in an OpenAPI (documented)

9 more unmet checks in the Agent Readiness table above.

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

Access Clarity scores 15.8 — up to +16.8 composite points
Developer Ergonomics scores 40.5 — up to +11.9 composite points
Operational Transparency scores 10.5 — up to +11.6 composite points

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.

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/litmus/apis.yml: open an issue on github.com/api-evangelist/litmus 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 →

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 7

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

Litmus Analytics API

Campaign engagement metrics and breakdowns

Litmus Campaigns API

Email campaign tracking and management

Litmus Clients API

Available email client configurations

Litmus Previews API

Email preview generation and management

Litmus Results API

Test result retrieval

Litmus Tests API

Email test creation and management

Litmus Ftp Sites API

The FtpSites API from Litmus — 1 operation(s) for ftpsites.

Scroll for all 7

Open Collections 7

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

Litmus Email Analytics API

OPEN COLLECTION

Litmus Email Analytics Campaigns API

OPEN COLLECTION

Litmus Email Analytics Clients API

OPEN COLLECTION

Litmus Email Analytics API

OPEN COLLECTION

Litmus Instant API

OPEN COLLECTION

Litmus Email Analytics Results API

OPEN COLLECTION

Litmus Email Analytics Tests API

OPEN COLLECTION

Scroll for all 7

Litmus API pricing

Not yet checked against Litmus's own pricing page. Compiled by API Evangelist on 2026-05-05 from www.litmus.com/pricing; confirm before you rely on a figure.

Plan	Price
Litmus Enterprise enterprise	—
Deliverability Upgrade subscription	—
Sender Certification Upgrade subscription	—
Competitive Intel Upgrade subscription	—
Email Guardian Upgrade subscription	—
Mailcharts Upgrade subscription	—
Litmus Instant API (Partner Program) enterprise	—

Plan details, limits and sources →

Rate limits

Partner API rate limit: see partner agreement varies
Bulk delete batch size: 1000 ids per request
Uploaded email retention window: 48 hours

Compiled by API Evangelist, not yet checked against Litmus's documentation. All 4 limits →

Pricing Plans 1

Published pricing tiers and plan structures.

Litmus Plans Pricing

7 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Litmus Rate Limits

4 limits

RATE LIMITS

Service Levels 1

Uptime the provider promises or reports, as SLA4OAI. Read from its own pages; APIs.io runs no monitors.

Litmus

SLA

FinOps 1

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

Litmus Finops

FINOPS

Semantic Vocabularies 1

JSON-LD contexts and semantic vocabularies used across these APIs.

Litmus Context

7 classes · 46 properties

JSON-LD

Spectral Rules 1

Spectral governance rulesets for linting and validating these APIs.

Litmus — jsonschema rules

6 rules · 5 warnings 1 info

SPECTRAL

JSON Schema 1

Standalone JSON Schema definitions for this provider's data models.

Litmus Email Test

13 properties

JSON SCHEMA

Security Posture 3

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

Litmus Authentication

http · 2 schemes

SECURITY

Litmus Domain Security

TLSv1.3 · HSTS · DMARC

SECURITY

Litmus Trust Center

SOC 2, ISO 27001, GDPR

SECURITY

Agentic Access 1

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

Litmus Agentic Access

21 operations · 5 acting

AGENTIC

Resources

Get Started 1

Portal, sign-up, and the first successful call

GettingStarted

GettingStarted

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

JSONSchema

JSONSchema

Agent Surfaces 1

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

Design & Contract 1

Pagination, idempotency, versioning, errors, and events

JSONLD

JSONLD

Build 1

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

GitHubOrganization

Access & Security 5

Authentication, authorization, and security posture

TrustCenter

DomainSecurity

Authentication

Authentication

Authentication

Operate 2

Status, limits, changes, and where to get help

RateLimits

RateLimits

Community

Community

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

CapabilityMap

CapabilityMap

Source (apis.yml)

aid: litmus
name: Litmus
description: Email testing and analytics platform that allows developers and marketers to preview, test, and analyze email
  campaigns across multiple email clients and devices before sending.
type: Index
deliveryModel:
  model: unknown
  open_source: false
  commercial: false
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: enterprise
  onboarding: unknown
  trial: false
  try_now: false
  public: false
  label: Enterprise
  confidence: medium
  source:
  - plans
  - authentication
  - security
  generated: '2026-11-06'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/litmus.png
x-docs-platform: vitepress
x-docs-platform-confidence: medium
x-docs-platform-checked: 2026-10-03
x-docs-hosting: github-pages
tags:
- Developer Tools
- Email Testing
- Marketing Tools
- Quality Assurance
- Email
url: https://raw.githubusercontent.com/api-evangelist/litmus/refs/heads/main/apis.yml
created: '2025-01-01'
modified: '2026-05-19'
specificationVersion: '0.23'
apis:
- aid: litmus:litmus-analytics-api
  name: Litmus Analytics API
  description: Campaign engagement metrics and breakdowns
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Analytics
  properties:
  - type: OpenAPI
    url: openapi/litmus-analytics-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-campaigns-api
  name: Litmus Campaigns API
  description: Email campaign tracking and management
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Campaigns
  properties:
  - type: OpenAPI
    url: openapi/litmus-campaigns-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-clients-api
  name: Litmus Clients API
  description: Available email client configurations
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Clients
  properties:
  - type: OpenAPI
    url: openapi/litmus-clients-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-previews-api
  name: Litmus Previews API
  description: Email preview generation and management
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Previews
  properties:
  - type: OpenAPI
    url: openapi/litmus-previews-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-results-api
  name: Litmus Results API
  description: Test result retrieval
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Results
  properties:
  - type: OpenAPI
    url: openapi/litmus-results-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-tests-api
  name: Litmus Tests API
  description: Email test creation and management
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - Tests
  properties:
  - type: OpenAPI
    url: openapi/litmus-tests-api-openapi.yml
  - type: Documentation
    url: https://docs.litmus.com/instant
  - type: Authentication
    url: https://docs.litmus.com/oauth-integration-guide
  - type: Documentation
    url: https://docs.litmus.com/legacy-previews
  - type: Documentation
    url: https://docs.litmus.com/email-analytics
- aid: litmus:litmus-ftpsites-api
  name: Litmus Ftp Sites API
  description: The FtpSites API from Litmus — 1 operation(s) for ftpsites.
  humanURL: https://docs.litmus.com/instant
  baseURL: https://instant-api.litmus.com/v1
  tags:
  - FtpSites
  properties:
  - type: OpenAPI
    url: openapi/litmus-ftpsites-api-openapi.yml
common:
- type: Plans
  url: plans/litmus-plans-pricing.yml
- type: RateLimits
  url: rate-limits/litmus-rate-limits.yml
- type: FinOps
  url: finops/litmus-finops.yml
- type: CapabilityMap
  url: capabilities/litmus-capability-edges.yml
  name: Litmus Business Capability Map
- type: AgenticAccess
  url: agentic-access/litmus-agentic-access.yml
- type: TrustCenter
  url: security/litmus-trust-center.yml
- type: DomainSecurity
  url: security/litmus-domain-security.yml
- type: Authentication
  url: authentication/litmus-authentication.yml
- type: GitHubOrganization
  url: https://github.com/litmus
- type: LinkedIn
  url: https://www.linkedin.com/company/litmus-com
- url: https://www.litmus.com/
  type: Website
- url: https://docs.litmus.com/
  type: Documentation
- url: https://www.litmus.com/getting-started/test-your-email
  type: GettingStarted
- url: https://www.litmus.com/blog/
  type: Blog
- url: https://litmus.com/community
  type: Community
- url: https://docs.litmus.com/oauth-integration-guide
  type: Authentication
- url: https://docs.litmus.com/oauth/web-application-flow
  type: Authentication
- type: JSONSchema
  url: json-schema/litmus-email-test-schema.json
  name: Litmus Email Test JSON Schema
  description: JSON Schema for Litmus email test objects covering preview, spam filter, and link-check test requests and results.
- type: JSONLD
  url: json-ld/litmus-context.jsonld
  name: Litmus JSON-LD Context
  description: Linked data context mapping Litmus email test and campaign entities to standard vocabularies.
- type: Integrations
  url: https://www.litmus.com/integrations
integrations:
- name: Litmus
- name: Wistia video thumbnail
- name: Litmus page view feature example
- name: TrustRadius
- name: Booking.com
- name: Ford
- name: LendingTree
- name: publicis Worldwide
- name: Johnson and Johnson
- name: Target
- name: Cisco
- name: Sony
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com

Litmus API — frequently asked questions

Does Litmus have an API?

Yes. APIs.io lists 7 APIs from Litmus, including Litmus Analytics API, Litmus Campaigns API and Litmus Clients API, and 4 more.

Is there an OpenAPI specification for the Litmus API?

Yes. APIs.io indexes 7 OpenAPI specifications for Litmus, each linked for download from this page.

How do I authenticate with the Litmus API?

Litmus uses bearer-token authentication (http · 2 schemes). The details are profiled on APIs.io as Litmus Authentication.

How much does the Litmus API cost?

APIs.io lists 7 pricing plans for Litmus, with each plan's price, limits and inclusions under Pricing on this page.

Is the Litmus API ready for AI agents?

Litmus has a Kin Score of 35.0 out of 100 (thin) and an Agent Readiness score of 24.4 (agent-aware), scored by API Evangelist on 2026-11-06.

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