Plunk

Plunk is an open-source (AGPL-3.0) email platform for developers that unifies transactional email, marketing campaigns, contact segmentation and event-driven workflow automation behind a single REST API. It publishes its own OpenAPI 3.1.0 at docs.useplunk.com/openapi.json, declaring next-api.useplunk.com as the production base URL, and authenticates with a two-class Bearer API key where the prefix decides capability — sk_ for every endpoint and pk_ for the client-safe /v1/track tracking call. The API supports Idempotency-Key on both public write endpoints, cursor pagination, a structured error envelope carrying machine codes plus remediation hints, and a documented webhook event catalogue delivered as workflow steps. Every documentation page is also served as Markdown. The entire stack self-hosts with Docker Compose for full data ownership and no per-email costs.

Plunk publishes 7 API contracts indexed on the APIs.io network, including Campaigns API, Contacts API, Events API, and 4 more. Tagged areas include Email, Transactional Email, Marketing, Automation, and Open Source.

The Plunk catalog on APIs.io includes 1 event-driven AsyncAPI specification and 1 Spectral governance ruleset.

Plunk’s developer surface includes authentication, documentation, changelog, API reference, getting-started guide, support, pricing, and 34 more developer resources.

🌐 Visit website 📡 Profile data on GitHub

75.0/100 exemplar ▬ flat Agent 42/100 agent native Front door AI 4/6 moderate Heartbeat 100/100 alive Full breakdown ↓
scored 2026-11-13 · rubric v0.28.0 · Show this score on your site →

AccessFreemiumSelf serve⚡ Free to try

2 published contracts 4 Agent Skills

Email Transactional Email Marketing Automation Open Source Software-as-a-Service Email API Webhook Segmentation Workflow Automation Self-Hosted Developer Tools

What this lets a business do 3

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

Application Communications

AE-150

Public APITransactional

POST /send POST /v1/verify

Customer Relationship Management

BC-420

ContactsSegments

GET /segments POST /segments POST /contacts POST /contacts/subscribe

Marketing Management

BC-400

Campaigns

POST /campaigns POST /campaigns/{id}/send

What people ask Plunk 7

The questions people put to an LLM, and the jobs they hand an agent, that Plunk's APIs answer — each one linked to the operation that does it. Generated by API Evangelist

Plunk Contacts API List contacts “Which contacts are on my Plunk mailing list?” Create or upsert a contact by email “How do I add a new contact to my list?” Update a contact by id in the request body “Is there an update endpoint where the contact id goes in the body rather than the URL?” Delete a contact by id in the request body “Can I delete a contact by sending its id in the request body?”

Plunk Campaigns API List email campaigns “Which email campaigns do I have in Plunk right now?” Create a new email campaign draft “How do I set up a new marketing email campaign?” Edit a draft campaign “Can I change the subject line of a campaign that's still a draft?” Delete a campaign “Can I permanently remove a campaign I no longer need?”

Plunk Public API Send a transactional email “How do I send a password reset email through Plunk?” Track an event for a contact “How do I log a custom event like a purchase against a contact?” Verify an email address “Can I check whether an email address is valid before I add it?”

Plunk Templates API List email templates “Which email templates do I have in Plunk?” Create an email template “How do I save a reusable email template with variable placeholders?”

Plunk Segments API List audience segments “Which audience segments have I set up in Plunk?” Create an audience segment “How do I create a segment that updates automatically as contact data changes?”

Plunk Transactional API Send a transactional email “How do I send a one-off transactional email with Plunk?”

Plunk Events API Track a named event for a contact “How do I record that a user signed up so my Plunk automations fire?”

Kin Score

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

Composite quality — 75.0/100 · exemplar

Contract Quality 12.5 / 19

Developer Ergonomics 9.7 / 15

Access Clarity 13.1 / 15

Operational Transparency 6.7 / 10

Contract Governance 2.9 / 9

Discoverability 5.5 / 8

Regulatory Posture 3.5 / 15

Create-or-Update Ergonomics 7.2 / 10

Agent readiness — 42/100 · agent native

Machine-Readable Contract 18 / 18

Agentic Access Contract 10 / 10

Documented Reversibility 0 / 6

MCP Server 0 / 12

Machine-Readable Auth 10 / 10

Idempotency 9 / 9

Stable Error Semantics 8 / 8

Request/Response Examples 7 / 7

Rate-Limit Signaling 7 / 7

Typed Event Surface 6 / 6

Agent Skills 5 / 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 5 / 5

Distinct Operations 0 / 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 →
A2A Agent Card +8 pts — a2a/-a2a.yml manifest, graded on conformance.grade against A2A 1.0.0 Ask about this →
Registration Without a Human +6 pts — a `registration_endpoint` in the served RFC 8414 / OIDC discovery document Ask about this →
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) Ask about this →
Documented Reversibility +6 pts — a reversal operation in the contract, graded up when a window is documented too Ask about this →
Protected Resource Metadata +5 pts — a served /.well-known/oauth-protected-resource carrying `resource` (documented), and naming its authorization_servers (verified) Ask about this →

5 more unmet checks in the Agent Readiness table above.

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

Contract Quality scores 66.8 — up to +8.3 composite points Ask about this →
Contract Governance scores 31.8 — up to +8.2 composite points Ask about this →
Developer Ergonomics scores 64.9 — up to +7.0 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.

Not sure how this applies to your stack? Ask about any one item. Kin Lane reads every question, looks at your profile and your situation, and replies with what a fix would take — scoped to that one area, priced up front, yours whether you ship it or not. Ask a question →

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/plunk/apis.yml: open an issue on github.com/api-evangelist/plunk 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
Communications (CPaaS)	covered	19.2 (thin)	-	-
Atlassian Marketplace (builders on Jira, Confluence, Bitbucket)	covered	19.2 (thin)	-	-

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 7

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

Plunk Campaigns API

Create and send marketing campaigns.

Plunk Contacts API

Manage contacts and their subscription state.

Plunk Events API

Track contact events that drive automations.

Plunk Transactional API

Send transactional email.

Plunk Public API

Public API endpoints for sending emails and tracking events

Plunk Segments API

Audience segmentation

Plunk Templates API

Email template management

Scroll for all 7

Open Collections 5

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

Plunk Campaigns API

OPEN COLLECTION

Plunk Campaigns Contacts API

OPEN COLLECTION

Plunk Campaigns Events API

OPEN COLLECTION

Plunk Campaigns Transactional API

OPEN COLLECTION

Plunk API

OPEN COLLECTION

Agent Skills 4

Packaged agent skills for driving this provider's APIs from an AI assistant.

Create and send a Plunk campaign to a segment

AGENT SKILL

Receive Plunk webhook events in your application

AGENT SKILL

Send a transactional email with Plunk

AGENT SKILL

Track an event and upsert a contact in Plunk

AGENT SKILL

Plunk API pricing

Prices published by Plunk, read 2026-10-28 from www.useplunk.com/pricing.

Plan	Price
Free forever	1,000 emails/ mo Includes: 1,000 emails / mo, no credit card required, Plunk branding on emails
Pay as you grow	$0.001/ email Includes: Everything in Free, no Plunk branding, monthly spend cap, unlimited emails
Self-hostable	Self-host for free Includes: Run on your own infrastructure, Docker Compose deploy

Plan details, limits and sources →

Rate limits

Requests Per Minute: ~1000 per minute requests
Email Sending Throttle: throttled per project emails
Bulk Operations: automatically queued jobs

Rate-limit details →

Billed by: emails · FinOps profile →

Pricing Plans 2

Published pricing tiers and plan structures.

Plunk Plans Pricing

3 plans

PLANS

Plunk Price Estimates

0 plans

PLANS

Rate Limits 1

Documented rate limits and quota policies.

Plunk Rate Limits

3 limits

RATE LIMITS

Terms of Service 1

What its API terms permit and prohibit, quoted from its own page.

Plunk

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

TERMS

Privacy & Data 1

Its role, the data it processes, retention and transfers, quoted from its own privacy page.

Plunk

24 quoted statements, read from Plunk's own page on 2026-11-10.

PRIVACY

Eligibility 1

Who may sign up and where, quoted from its own terms.

Plunk

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

ELIGIBILITY

Data License 1

How its data and outputs may be reused, quoted from its own terms.

Plunk

2 quoted statements, read from Plunk's own page on 2026-11-10.

LICENSE

FinOps 1

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

Plunk Finops

FINOPS

Event Specifications 1

AsyncAPI definitions for this provider's event-driven and streaming APIs.

Plunk Webhooks

ASYNCAPI

Spectral Rules 1

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

Plunk API Rules

63 rules · 59 error-severity 3 warn-severity 1 info-severity

SPECTRAL

OpenAPI Overlays 8

Overlays applied on top of this provider's contracts. Each card says who wrote it: a document the provider publishes, or one API Evangelist derived or generated.

Plunk Api Overlay

9 actions · update · plunk-api-openapi.json

DERIVED

Plunk Campaigns Api Phrasing Overlay

7 actions · phrasing · plunk-campaigns-api-openapi.yml

GENERATED

Plunk Contacts Api Phrasing Overlay

11 actions · phrasing · plunk-contacts-api-openapi.yml

GENERATED

Plunk Events Api Phrasing Overlay

2 actions · phrasing · plunk-events-api-openapi.yml

GENERATED

Plunk Public Api Api Phrasing Overlay

4 actions · phrasing · plunk-public-api-api-openapi.yml

GENERATED

Plunk Segments Api Phrasing Overlay

3 actions · phrasing · plunk-segments-api-openapi.yml

GENERATED

Plunk Templates Api Phrasing Overlay

3 actions · phrasing · plunk-templates-api-openapi.yml

GENERATED

Plunk Transactional Api Phrasing Overlay

2 actions · phrasing · plunk-transactional-api-openapi.yml

GENERATED

Scroll for all 8

Security Posture 2

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

Plunk Authentication

http · 1 scheme

SECURITY

Plunk Domain Security

TLSv1.3 · DMARC

SECURITY

Agentic Access (API Evangelist recommendations) 1

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

Plunk Agentic Access

25 operations · 19 acting

AGENTIC

Resources

Get Started 4

Portal, sign-up, and the first successful call

DeveloperPortal

DeveloperPortal

GettingStarted

GettingStarted

SignUp

SignUp

Login

Documentation 2

Reference material describing how the API behaves

Documentation

Documentation

APIReference

APIReference

Agent Surfaces 3

MCP servers, agent skills, and machine-readable catalogs

AgenticAccess

AgenticAccess

LLMsTxt

LLMsTxt

AgentSkill

AgentSkill

Design & Contract 7

Pagination, idempotency, versioning, errors, and events

Conventions

Idempotency

ErrorCatalog

Lifecycle

DataModel

Webhooks

Conformance

Scroll for all 7

Build 4

SDKs, sample code, and the tooling you integrate with

GitHubOrganization

Packages

SDKs

SourceCode

Access & Security 3

Authentication, authorization, and security posture

DomainSecurity

DomainSecurity

Authentication

Authentication

Compliance

Compliance

Operate 4

Status, limits, changes, and where to get help

RateLimits

StatusPage

ChangeLog

Support

Commercial 8

Pricing, plans, and the legal terms of use

License

Plans

FinOps

Pricing

TermsOfService

PrivacyPolicy

UsageTerms

DataLicense

Scroll for all 8

Company 2

The organization behind the API

LinkedIn

Website

Website

Other 4

Properties that don't map to a standard resource type

CapabilityMap

Overlay

DataProcessing

Eligibility

Source (apis.yml)

aid: plunk
url: https://raw.githubusercontent.com/api-evangelist/plunk/refs/heads/main/apis.yml
name: Plunk
kind: company
description: Plunk is an open-source (AGPL-3.0) email platform for developers that unifies transactional email, marketing
  campaigns, contact segmentation and event-driven workflow automation behind a single REST API. It publishes its own OpenAPI
  3.1.0 at docs.useplunk.com/openapi.json, declaring next-api.useplunk.com as the production base URL, and authenticates with
  a two-class Bearer API key where the prefix decides capability — sk_ for every endpoint and pk_ for the client-safe /v1/track
  tracking call. The API supports Idempotency-Key on both public write endpoints, cursor pagination, a structured error envelope
  carrying machine codes plus remediation hints, and a documented webhook event catalogue delivered as workflow steps. Every
  documentation page is also served as Markdown. The entire stack self-hosts with Docker Compose for full data ownership and
  no per-email costs.
deliveryModel:
  model: unknown
  open_source: unknown
  commercial: true
  callable_host: true
  label: Delivery model not determined — needs a product licence on record
  confidence: low
  source:
  - openapi
  - pricing
  - repository-unlicensed
  generated: '2026-08-28'
  method: derived
accessModel:
  pricing: freemium
  onboarding: self-serve
  trial: false
  try_now: true
  public: false
  gated: none
  gated_source:
  - onboarding
  label: Freemium · Self-serve signup
  confidence: high
  source:
  - plans
  - authentication
  - rate-limits
  - security
  generated: '2026-11-13'
  method: derived
image: https://kinlane-images.s3.amazonaws.com/shared/apis-json/icons/plunk.png
tags:
- Email
- Transactional Email
- Marketing
- Automation
- Open Source
- Software-as-a-Service
- Email API
- Webhook
- Segmentation
- Workflow Automation
- Self-Hosted
- Developer Tools
tags_raw:
- Email
- Transactional Email
- Marketing
- Automation
- Open Source
- SaaS
- Email API
- Webhooks
- Segmentation
- Workflow Automation
- Self-Hosted
- Developer Tools
- Open-Source
- Workflow-Automation
created: '2026-06-20'
modified: '2026-08-13'
specificationVersion: '0.23'
apis:
- aid: plunk:plunk-campaigns-api
  name: Plunk Campaigns API
  description: Create and send marketing campaigns.
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://next-api.useplunk.com
  baseurl_source: contract
  tags:
  - Campaigns
  properties:
  - type: OpenAPI
    url: openapi/plunk-campaigns-api-openapi.yml
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/send
  - type: APIReference
    url: https://docs.useplunk.com/api-reference/overview
  - type: PostmanCollection
    url: collections/plunk.postman_collection.json
  - type: OpenCollection
    url: collections/plunk.opencollection.json
  - type: GitHub
    url: https://github.com/useplunk/plunk
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/track
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/contacts/create
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/campaigns/create
- aid: plunk:plunk-contacts-api
  name: Plunk Contacts API
  description: Manage contacts and their subscription state.
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://next-api.useplunk.com
  baseurl_source: contract
  tags:
  - Contacts
  properties:
  - type: OpenAPI
    url: openapi/plunk-contacts-api-openapi.yml
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/send
  - type: APIReference
    url: https://docs.useplunk.com/api-reference/overview
  - type: PostmanCollection
    url: collections/plunk.postman_collection.json
  - type: OpenCollection
    url: collections/plunk.opencollection.json
  - type: GitHub
    url: https://github.com/useplunk/plunk
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/track
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/contacts/create
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/campaigns/create
- aid: plunk:plunk-events-api
  name: Plunk Events API
  description: Track contact events that drive automations.
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://api.useplunk.com/v1
  tags:
  - Event
  tags_raw:
  - Events
  properties:
  - type: OpenAPI
    url: openapi/plunk-events-api-openapi.yml
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/send
  - type: APIReference
    url: https://docs.useplunk.com/api-reference/overview
  - type: PostmanCollection
    url: collections/plunk.postman_collection.json
  - type: OpenCollection
    url: collections/plunk.opencollection.json
  - type: GitHub
    url: https://github.com/useplunk/plunk
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/track
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/contacts/create
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/campaigns/create
- aid: plunk:plunk-transactional-api
  name: Plunk Transactional API
  description: Send transactional email.
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://api.useplunk.com/v1
  tags:
  - Transactional
  properties:
  - type: OpenAPI
    url: openapi/plunk-transactional-api-openapi.yml
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/send
  - type: APIReference
    url: https://docs.useplunk.com/api-reference/overview
  - type: PostmanCollection
    url: collections/plunk.postman_collection.json
  - type: OpenCollection
    url: collections/plunk.opencollection.json
  - type: GitHub
    url: https://github.com/useplunk/plunk
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/transactional/track
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/contacts/create
  - type: Documentation
    url: https://docs.useplunk.com/api-reference/campaigns/create
- aid: plunk:plunk-public-api-api
  name: Plunk Public API
  description: Public API endpoints for sending emails and tracking events
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://next-api.useplunk.com
  baseurl_source: contract
  tags:
  - Public APIs
  tags_raw:
  - Public API
  properties:
  - type: OpenAPI
    url: openapi/plunk-public-api-api-openapi.yml
- aid: plunk:plunk-segments-api
  name: Plunk Segments API
  description: Audience segmentation
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://next-api.useplunk.com
  baseurl_source: contract
  tags:
  - Segments
  properties:
  - type: OpenAPI
    url: openapi/plunk-segments-api-openapi.yml
- aid: plunk:plunk-templates-api
  name: Plunk Templates API
  description: Email template management
  humanURL: https://docs.useplunk.com/api-reference/transactional/send
  baseURL: https://next-api.useplunk.com
  baseurl_source: contract
  tags:
  - Templates
  properties:
  - type: OpenAPI
    url: openapi/plunk-templates-api-openapi.yml
common:
- type: CapabilityMap
  url: capabilities/plunk-capability-edges.yml
  name: Plunk Business Capability Map
- type: License
  name: AGPL-3.0
  url: https://github.com/useplunk/plunk/blob/next/LICENSE
- type: AgenticAccess
  url: agentic-access/plunk-agentic-access.yml
- type: DomainSecurity
  url: security/plunk-domain-security.yml
- type: Authentication
  url: authentication/plunk-authentication.yml
- type: GitHubOrganization
  url: https://github.com/useplunk
- type: LinkedIn
  url: https://www.linkedin.com/company/useplunk
- type: Website
  url: https://www.useplunk.com
- type: Documentation
  url: https://docs.useplunk.com
- type: Plans
  url: plans/plunk-plans-pricing.yml
- type: RateLimits
  url: rate-limits/plunk-rate-limits.yml
- type: FinOps
  url: finops/plunk-finops.yml
- type: Packages
  url: packages/plunk-packages.yml
- type: SDKs
  url: packages/plunk-packages.yml
- type: LLMsTxt
  url: llms/plunk-llms.txt
- type: Overlay
  url: overlays/plunk-api-overlay.yaml
- type: Conventions
  url: conventions/plunk-conventions.yml
- type: Idempotency
  url: conventions/plunk-conventions.yml
- type: ErrorCatalog
  url: errors/plunk-problem-types.yml
- type: Lifecycle
  url: lifecycle/plunk-lifecycle.yml
- type: StatusPage
  url: https://status.useplunk.com
- type: ChangeLog
  url: changelog/plunk-changelog.yml
- type: DataModel
  url: data-model/plunk-data-model.yml
- type: Webhooks
  url: asyncapi/plunk-webhooks.yml
- type: AgentSkill
  url: skills/_index.yml
- type: Conformance
  url: conformance/plunk-conformance.yml
- type: Compliance
  url: https://www.useplunk.com/dpa
- type: DeveloperPortal
  url: https://docs.useplunk.com
- type: APIReference
  url: https://docs.useplunk.com/api-reference/overview
- type: GettingStarted
  url: https://docs.useplunk.com
- type: Support
  url: https://www.useplunk.com/discord
- type: Pricing
  url: https://www.useplunk.com/pricing
- type: SignUp
  url: https://next-app.useplunk.com/auth/signup
- type: Login
  url: https://next-app.useplunk.com/auth/login
- type: TermsOfService
  url: https://www.useplunk.com/terms
- type: PrivacyPolicy
  url: https://www.useplunk.com/privacy
- type: SourceCode
  url: https://github.com/useplunk/plunk
- type: UsageTerms
  url: terms/plunk-terms-of-service.yml
- type: DataProcessing
  url: privacy/plunk-privacy-policy.yml
- type: Eligibility
  url: eligibility/plunk-eligibility.yml
- type: DataLicense
  url: data-license/plunk-data-license.yml
maintainers:
- FN: Kin Lane
  email: kin@apievangelist.com
x-enrichment:
  date: '2026-08-13'
  status: enriched
  artifacts_added: 19
  pass: local-v1

Plunk API — frequently asked questions

Does Plunk have an API?

Yes. APIs.io lists 7 APIs from Plunk, including Plunk Campaigns API, Plunk Contacts API and Plunk Events API, and 4 more.

Is there an OpenAPI specification for the Plunk API?

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

How do I authenticate with the Plunk API?

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

How much does the Plunk API cost?

Plunk publishes its prices; its Free forever plan is 1,000 emails/ mo as of 2026-10-28. APIs.io lists 3 pricing plans for Plunk, with each plan's price, limits and inclusions under Pricing on this page.

Is the Plunk API ready for AI agents?

Plunk has a Kin Score of 75.0 out of 100 (exemplar) and an Agent Readiness score of 41.7 (agent-native), scored by API Evangelist on 2026-11-13.

Work with this as data

Every provider here is available over the APIs.io API and to AI agents over MCP.

MCP server

One button, every client — Claude, Cursor, VS Code and the rest.

https://apis.io/mcp

Tools for providers

9 MCP tools reach this

find_providersBrowse and filter every provider in the catalog.
get_provider_artifactsEvery artifact this provider publishes, grouped by type.
get_provider_operationsEvery operation across all of their OpenAPIs — one call instead of parsing every spec.
get_provider_toolsEvery MCP tool they ship, with the operation each wraps.
get_provider_evidenceHow each part of their score was established. Free — the basis for a claim should not sit behind it.
get_provider_ratingPRO — composite, band, trend and facet scores.
apis_io_searchSTART HERE — APIs, providers and tags for one query, each with its total.
resolveTurn a domain, URL or GitHub org into the provider it belongs to.
find_cohortsEvery scored population of providers in the catalog.

All 92 tools →

Call it yourself

curl for this page

This provider

curl "https://apis.io/api/v1/providers/plunk"

All providers

curl "https://apis.io/api/v1/providers?limit=25"

Every operation they expose

curl "https://apis.io/api/v1/providers/plunk/operations?limit=25"

How their score was established

curl "https://apis.io/api/v1/providers/plunk/evidence"

Calls without X-API-Key need no key. Calls with it need a paid plan — get a key.

Get an API key

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A second provider on the same verified email joins the account you already have.