Curated
Treblle
Platform for monitoring and governing API traffic and design
API MonitoringAPI intelligence platform
APIs
API clients, design tools and gateways for building and testing APIs.
80 tools
Latest Tools
6 toolsFreemium
Alpha Vantage
Stock market, forex and crypto data API with a free API key
Public APIsFree stock market API
Open source
Free trial
Arcjet
Security for web apps and AI agents: bots, abuse, prompts
API SecurityRate limiting and bot defense
Freemium
Beeceptor
Hosted mock server builder for REST, SOAP, GraphQL and gRPC APIs
Mocking TestingHosted mock APIs
Open source
Frankfurter
Free exchange rate API for 219 currencies, with history back to 1948
Public APIsFree currency exchange rates
API Clients
7 toolsFreemium
Apidog
All-in-one API platform for design, testing, mocking and docs
API ClientsAll in one API platform
Open source
Hoppscotch
Open source web app for building and testing API requests
API ClientsOpen source API tester
Open source
HTTPie
Friendly command-line and desktop client for testing HTTP APIs
API ClientsFriendly HTTP clientInactive
Open source
Insomnia
Open source desktop client for testing HTTP, GraphQL and gRPC APIs
API ClientsOpen source API client
Curated
Requestly
Desktop API client with local projects, mocks and Postman import
API ClientsIntercept and mock requests
Freemium
Thunder Client
Fast REST and GraphQL API client for VS Code and JetBrains IDEs
API ClientsLightweight VS Code API client
Open source
Yaak
Local-first desktop API client that stores requests as files in Git
API ClientsFast desktop API client
API Design
4 toolsOpen source
OpenAPI
Open standard for describing HTTP APIs in a machine-readable way
API DesignThe OpenAPI standard
Freemium
Stoplight
Visual platform for designing, documenting and mocking OpenAPI
API DesignAPI design and docs platform
Popular
Swagger
Open source tools for designing and documenting OpenAPI APIs
API DesignOpenAPI docs and tooling
Open source
Zod
TypeScript-first schema validation with static type inference
API DesignTypeScript schema validation
API Gateways
5 tools
API Monitoring
2 tools
API Security
3 toolsCurated
Free trial
Arcjet
Security for web apps and AI agents: bots, abuse, prompts
API SecurityRate limiting and bot defense
Curated
Salt Security
Security platform for APIs and AI agents that call them
API SecurityAPI threat protection
API Services
1 toolOpen source
Kong
Open source API gateway for securing and managing API traffic
API ServicesOpen source API gateway
Design and SDKs
9 toolsFreemium
Apiary
Hosted platform to design, prototype, document and test APIs
Design and SDKsAPI design and docs platform
Open source
AsyncAPI
Open source specification and tools for event-driven APIs
Design and SDKsSpec for event driven APIs
Curated
Bump.sh
Hosted API docs and MCP servers, built from your OpenAPI spec
Design and SDKsAPI docs with changelogs
Freemium
Fern
Generate SDKs, API docs and a CLI from an OpenAPI spec
Design and SDKsSDKs and docs from your API
Open source
Joi
Schema description and validation library for JavaScript objects
Design and SDKsSchema validation for JS
Popular
JSON Schema
Standard vocabulary for describing and validating JSON data
Design and SDKsStandard for JSON validation
Open source
OpenAPI Generator
Generates API clients, server stubs and docs from OpenAPI
Design and SDKsGenerate clients from OpenAPI
Open source
Scalar
Hosted API docs, typed SDKs and MCP servers from an OpenAPI file
Design and SDKsModern OpenAPI docs and client
Open source
TypeSpec
Code-first language to define APIs and emit OpenAPI or JSON Schema
Design and SDKsDesign APIs with code
GraphQL and RPC
12 toolsOpen source
Altair GraphQL Client
Feature-rich desktop and web client for debugging GraphQL servers
GraphQL and RPCFeature rich GraphQL client
Freemium
Apollo GraphQL
Platform to build and run one graph over your existing APIs
GraphQL and RPCGraphQL client and server tool
Open source
Buf
Toolchain for Protobuf and gRPC with linting and code generation
GraphQL and RPCModern Protobuf tooling
Open source
Connect
Protobuf RPC library for browser and gRPC-compatible APIs
GraphQL and RPCBrowser friendly gRPC
Open source
Open source
GraphQL Code Generator
Generates typed clients, resolvers and SDKs from a GraphQL schema
GraphQL and RPCGenerate types from GraphQL
Open source
GraphQL Yoga
Cross-platform GraphQL server with plugins, caching and rate limiting
GraphQL and RPCFully featured GraphQL server
Open source
gRPC
Open source high performance RPC framework using Protocol Buffers
GraphQL and RPCHigh performance RPC framework
Open source
PostGraphile
Extensible GraphQL API built on top of PostgreSQL databases
GraphQL and RPCGraphQL from Postgres
Open source
Relay
GraphQL client for React apps that scales with large codebases
GraphQL and RPCGraphQL client by Meta
Open source
tRPC
Typesafe APIs shared between a TypeScript server and client
GraphQL and RPCEnd-to-end typesafe APIs
Open source
WunderGraph Cosmo
Open source GraphQL federation platform for supergraphs
GraphQL and RPCGraphQL federation platform
Integration Platforms
8 toolsOpen source
Apache Camel
Open source framework with 350+ connectors for integration routes
Integration PlatformsOpen source integration
Free trial
Boomi
Cloud platform for integration, APIs, data and AI agents
Integration PlatformsCloud integration platform
Free trial
Celigo
Integration platform for connecting apps, data and AI workflows
Integration PlatformsiPaaS for business apps
Curated
Merge
Connects AI agents and apps to company data and tools
Integration PlatformsUnified API for integrations
Open source
Nango
Platform for product integrations and OAuth across 1,000+ APIs
Integration PlatformsProduct integrations and OAuth
Freemium
Paragon
Embedded integration platform for AI agents and SaaS products
Integration PlatformsEmbedded integrations platform
Free trial
Tray.ai
Low-code platform for integrations, automations and AI agents
Integration PlatformsLow code integration platform
Freemium
Workato
Enterprise platform to connect apps, data, AI agents and workflows
Integration PlatformsEnterprise automation platform
Mocking Testing
12 toolsFreemium
Beeceptor
Hosted mock server builder for REST, SOAP, GraphQL and gRPC APIs
Mocking TestingHosted mock APIs
Open source
Open source
Open source
Microcks
Cloud native open source tool for API mocking and testing
Mocking TestingAPI mocking and testing
Open source
Mock Service Worker
API mocking library for browser and Node.js
Mocking TestingMock APIs at network level
Open source
Mockoon
Create and run mock APIs locally with free open-source tools
Mocking TestingLocal mock API server
Open source
MockServer
Open source mock, proxy and recording server for HTTP and gRPC
Mocking TestingMock and proxy HTTP
Open source
Pact
Consumer-driven contract testing for APIs, web apps and microservices
Mocking TestingConsumer driven contract tests
Open source
REST Assured
Java library for testing and validating REST APIs with simple syntax
Mocking TestingJava REST API testing
Open source
Schemathesis
Open source tool that tests APIs by generating cases from schemas
Mocking TestingProperty based API testing
Open source
Step CI
Open source API testing framework with YAML workflows and CI support
Mocking TestingAPI testing and monitoringInactive
Open source
WireMock
Open source tool for simulating APIs in tests and development
Mocking TestingAPI mocking and simulation
Public APIs
13 toolsFreemium
Alpha Vantage
Stock market, forex and crypto data API with a free API key
Public APIsFree stock market API
Curated
API Ninjas
Collection of production-ready data APIs with a free API key
Public APIsCollection of useful APIs
Freemium
APILayer
Marketplace of 40+ APIs for finance, weather, geolocation and data
Public APIsReady to use APIs
Open source
Freemium
ExchangeRate-API
Currency exchange rate API for 165 currencies with a free plan
Public APIsCurrency conversion API
Open source
Frankfurter
Free exchange rate API for 219 currencies, with history back to 1948
Public APIsFree currency exchange rates
Open source
httpbin
Simple HTTP service that echoes requests and returns test responses
Public APIsHTTP request testing serviceInactive
Open source
JSONPlaceholder
Free fake REST API with six resources and no signup required
Public APIsFree fake REST APIInactive
Open source
Open-Meteo
Free weather forecast and historical weather API with no API key
Public APIsFree open weather API
Freemium
OpenWeather
Weather, forecast and air quality APIs with a free daily tier
Public APIsWeather data and forecasts
Open source
Freemium
ReqRes
Free hosted REST API for testing and prototyping with real responses
Public APIsHosted test REST API
Curated
REST Countries
Country data API with 250+ countries and 90+ fields per record
Public APIsCountry data over REST
Webhooks Tunnels
4 toolsOpen source
localtunnel
Free tool that gives a local web server a public URL
Webhooks TunnelsFree localhost tunnelsInactive
Open source
Freemium
Webhook.site
Generate unique URLs and emails to inspect incoming webhooks
Webhooks TunnelsInspect webhooks instantly
Open source
zrok
Open source tool to share local apps and files through tunnels
Webhooks TunnelsOpen source sharing tunnels