Feature

Open Source

Source code published under an open license.

114 providers 452 APIs 110 declared variants

The implementation is openly licensed and publicly readable, so integrators can audit behavior, fork, and contribute. Also changes the risk calculus on vendor continuity.

114 API providers on the APIs.io network offer open source. The highest-rated are Canvas LMS, Outbrain, GitLab, Commerce Layer, Airbyte.

Providers

Ranked by API Evangelist rating — Exemplar and Strong are expanded by default.

Exemplar 5 Complete, well-documented, and agent-ready
Strong 30 Solid coverage with minor gaps
Microsoft Azure QuantumMicrosoft Azure Quantum is Microsoft's cloud quantum computing service — an open, multi-vendor platform tha...2 APIs66.3CumulocityCumulocity is an enterprise AIoT (Artificial Intelligence of Things) platform that connects, manages, and a...17 APIs66.2E2BE2B (e2b-dev) provides secure, isolated cloud sandboxes for AI agents and AI-generated code, built on a for...3 APIs65.5Highlight (highlight.io)Highlight (highlight.io) is the open-source, full-stack monitoring platform — session replay, error monitor...5 APIs65.3BuildkiteBuildkite is a hybrid CI/CD platform that combines a hosted control plane (pipelines.buildkite.com) with se...2 APIs65.2PaperspacePaperspace is a GPU cloud platform for AI, ML, and 3D rendering workloads, acquired by DigitalOcean in 2023...4 APIs65.1IBM QuantumIBM Quantum is IBM's quantum computing program — the operator of the IBM Quantum Platform (quantum.cloud.ib...6 APIs64.4FireblocksFireblocks is an institutional digital-asset and stablecoin infrastructure company providing MPC-secured cu...7 APIs64.3n8nn8n is a fair-code workflow automation and iPaaS platform with AI-agent tooling. It exposes an instance-sco...1 API64.3DaytonaDaytona is open-source, secure, and elastic infrastructure for running AI-generated code. Daytona sandboxes...12 APIs63.5StytchStytch is an authentication and identity infrastructure provider. Its Consumer and B2B APIs cover passwordl...3 APIs63.5AnkrAnkr is a Web3 infrastructure provider whose multichain RPC, Advanced API, liquid staking, contract automat...4 APIs62.8ThingsBoardThingsBoard is an open-source IoT platform for device connectivity, data collection, processing, and visual...15 APIs62.4D-WaveD-Wave Quantum Inc. (NYSE: QBTS) is the leader in commercial quantum annealing computing and developer of t...4 APIs61.5UmamiUmami is an open source, privacy-first web analytics platform that provides website traffic insights withou...7 APIs61.2MewsMews is a cloud-native hospitality operating system serving 15,000+ hotels, hostels, and vacation-rental pr...3 APIs60.5HyperbolicHyperbolic is an open-access AI cloud and decentralized GPU marketplace serving 200,000+ builders with affo...5 APIs59.4NanonetsNanonets is a no-code document AI and OCR platform that combines a custom-model OCR API, pre-built document...3 APIs58.7Leonardo.AILeonardo.AI is an Australian generative-AI company (acquired by Canva in July 2024) offering a Production A...14 APIs57.7Google Quantum AIGoogle Quantum AI is Google's quantum-computing research and engineering arm, building superconducting quan...1 API57.3Pocket NetworkPocket Network is the decentralized RPC layer of Web3 — a permissionless, fully open data delivery protocol...3 APIs57.3DescopeDescope is a customer and agentic identity access management (CIAM) platform founded in 2022 by veterans of...1 API56.2LichessLichess is a free, ad-free, open-source online chess server operated by a French nonprofit and powered enti...1 API55.9CivitaiCivitai is the largest open community for Stable Diffusion, SDXL, Flux, and video AI models — hosting over ...2 APIs55.7Octopus EnergyOctopus Energy is a UK-founded retail energy supplier and the parent of Kraken Technologies, the AI-powered...1 API55.2Beatoven.aiBeatoven.ai is an Indian generative-music startup (Bengaluru, founded 2021) building text-to-music and text...1 API55.1Academy Software FoundationThe Academy Software Foundation (ASWF) is a Linux Foundation project that supports open source software dev...14 APIs55.0BackpackBackpack is a Solana-first crypto company founded by Armani Ferrante and Tristan Yver — the same team behin...1 API54.9ConektaConekta is a Mexico-based payment processor that lets businesses accept credit and debit cards, OXXO cash v...1 API54.9PipedreamPipedream is a developer-centric integration platform providing three product lines: Workflows (code-level ...2 APIs54.7
Developing 30 Usable, with meaningful gaps to close
EncoreEncore is a backend application framework and developer cloud that lets engineering teams build type-safe d...2 APIs54.0TIDALTIDAL is a high-fidelity music streaming service owned by Block (Square's parent, acquired 2021) offering H...8 APIs53.0VespaVespa is an open-source AI search engine, big-data serving engine, and vector database originally developed...3 APIs52.61NCE1NCE is a Cologne-headquartered global IoT connectivity provider best known for the IoT Lifetime Flat — a s...8 APIs52.4ServiceTitanServiceTitan is the operating system for the trades — all-in-one field service management software for resi...8 APIs52.1TensorTensor is the Solana-native NFT marketplace and trading protocol founded by Tensor HQ and now stewarded by ...2 APIs51.7arXivarXiv is the open-access e-print repository operated by Cornell Tech, hosting more than two million preprin...2 APIs51.5ContinueContinue is the open-source AI code assistant for VS Code and JetBrains, distributed under Apache 2.0. The ...1 API50.0WooCommerceWooCommerce is the world's most popular open-source eCommerce platform, built on WordPress. It provides a c...2 APIs49.4ChromaChroma (Chroma DB) is an open-source AI-native embedding database designed to make it easy to build LLM app...2 APIs49.3LangWatchLangWatch is an open-source LLM observability, evaluation, and AI agent testing platform. Built around Open...1 API47.9Triton OneTriton One is a high-performance Solana RPC and blockchain infrastructure provider operating globally distr...3 APIs47.9PackagistPackagist is the default package repository for Composer, the PHP dependency manager. It indexes over 454,0...1 API46.1Radio BrowserRadio Browser is a free, community-driven directory of internet radio stations. The project publishes a pub...1 API46.1VA LighthouseVA Lighthouse is the US Department of Veterans Affairs' developer API platform. Published at developer.va.g...22 APIs45.4PokéAPIPokéAPI (pokeapi.co) is a free, open-source RESTful and GraphQL API serving comprehensive Pokémon data — in...1 API44.8ForethoughtForethought is a San Francisco-based generative AI customer-support platform. Its multi-agent product suite...2 APIs44.5NangoNango.dev is a developer infrastructure platform that simplifies building product integrations with externa...1 API44.5OpenHandsOpenHands (by All Hands AI, formerly OpenDevin) is an open-source autonomous coding agent platform. Ships a...1 API43.6ApiaryApiary is an API design and documentation platform, now part of Oracle Cloud Infrastructure. With 486,000+ ...1 API42.9Children's Hospital of PhiladelphiaFounded in 1855 as the first hospital in the United States dedicated to the healthcare of children, Childre...1 API42.7CHAOSSCHAOSS (Community Health Analytics in Open Source Software) is a Linux Foundation project that develops met...2 APIs42.6Analog DevicesAnalog Devices (ADI) is a global semiconductor company designing high-performance analog, mixed-signal, and...4 APIs42.5CerbosCerbos is an open-core, language-agnostic, scalable authorization platform that decouples access control fr...1 API42.4TypesenseTypesense is a fast, typo-tolerant, open-source search engine designed for developer productivity. It provi...2 APIs42.1ipifyipify operates two complementary IP APIs. The free Public IP Address API (api.ipify.org, api6.ipify.org, ap...3 APIs41.2AgStack FoundationAgStack Foundation is a Linux Foundation project providing open-source digital infrastructure for the agric...3 APIs40.6RedisRedis is an open source, in-memory data structure store used as a database, cache, message broker, and stre...4 APIs40.6FrankfurterFrankfurter is an open-source (MIT) currency exchange rates API that blends foreign-exchange reference rate...2 APIs40.4crates.iocrates.io is the official package registry for the Rust programming language, operated by the crates.io tea...2 APIs40.1
Thin 24 Limited public surface area
KreaKrea is a real-time AI creative suite that lets designers, filmmakers, brand teams, and everyday creators g...1 API39.2DoclingDocling is an open-source toolkit for parsing diverse document formats — PDF, DOCX, PPTX, XLSX, HTML, image...2 APIs37.9SyndicaSyndica is a Solana-only infrastructure company building developer infrastructure for Web3. Its production ...4 APIs37.7ACI.devACI.dev (Aipolabs Agent-Computer Interface) is an open-source tool-calling platform that hooks AI agents in...1 API36.8TurborepoTurborepo is a high-performance build system for JavaScript and TypeScript codebases, built by Vercel and w...1 API36.5Quote GardenQuote Garden is a free, open-source REST API that serves more than 75,000 famous quotes. Built by Prathames...1 API34.0McKinsey & CompanyMcKinsey & Company is the senior partner of the MBB triumvirate of global strategy and management consultin...33.6JitsiJitsi is a collection of free and open-source projects for secure, simple, and scalable real-time video con...10 APIs33.5FormantFormant is a San Francisco–based robotics and physical-operations cloud platform that lets companies operat...1 API33.2CieloCielo is one of the largest Brazilian card acquirers and a publicly traded company (B3:CIEL3), originally f...13 APIs33.1Cypress SemiconductorCypress Semiconductor was a US-based semiconductor company known for its PSoC programmable system-on-chip m...6 APIs32.6AudiomackAudiomack is an on-demand music streaming and audio discovery platform that lets artists and creators uploa...1 API32.5Random User GeneratorFree random user data API for generating realistic fake user profiles with names, addresses, photos, and co...1 API31.2XanaduXanadu is a Canadian photonic quantum computing company building room-temperature, fault-tolerant, scalable...14 APIs31.2Eyevinn TechnologyEyevinn Technology is a Stockholm, Sweden based video streaming consultancy and open source company special...8 APIs31.0ApivaultApivault is an open-source directory and gateway for discovering public APIs. The platform catalogs thousan...1 API30.9American AirlinesAmerican Airlines is one of the world's largest airlines, operating an extensive domestic and international...1 API30.4GlamaGlama is an all-in-one AI workspace combining an MCP server marketplace and registry, a managed MCP gateway...7 APIs30.3BMW ConnectedDriveBMW ConnectedDrive is BMW Group's umbrella for connected vehicle services spanning navigation, remote servi...1 API30.1Volvo CarsVolvo Cars is a Swedish premium automotive OEM (headquartered in Gothenburg, owned by Geely) that operates ...4 APIs29.7RenovateRenovate is an open source automated dependency update bot maintained by Mend. It scans repositories for re...6 APIs28.9Deutsche TelekomDeutsche Telekom AG is Europe's largest telecommunications operator, headquartered in Bonn, Germany, servin...8 APIs28.7FirelyFirely is an Amsterdam-based health IT company and one of the original co-developers of the HL7 FHIR (Fast ...1 API27.8YarnYarn is an open-source JavaScript package manager and project manager originally created at Facebook in 201...10 APIs26.5
Emerging 20 Early or largely undocumented
SignifydSignifyd is an ecommerce fraud prevention, chargeback protection, and revenue optimization platform. Its Co...8 APIs26.1RakenRaken is a San Diego-based construction technology company providing a field-first daily reporting and fiel...1 API25.9ScenarioScenario is a Paris- and San Francisco-headquartered AI platform for game asset generation founded in 2021 ...5 APIs25.9Three.jsThree.js is an open-source JavaScript 3D library originally created by Ricardo Cabello (mrdoob) in 2010 and...6 APIs25.7WhyLabsWhyLabs was an AI observability platform focused on data and model monitoring for both classical ML and LLM...3 APIs25.2QuEra ComputingQuEra Computing is a Boston-based neutral-atom quantum computing company (founded 2018) that operates Aquil...8 APIs23.9SSTSST is an open source TypeScript framework for building full-stack applications on your own infrastructure....2 APIs22.7QuantinuumQuantinuum is an integrated quantum computing company formed by the 2021 merger of Honeywell Quantum Soluti...9 APIs22.1CasdoorCasdoor is an open-source, AI-first identity and access management (IAM) and MCP gateway authentication ser...1 API20.8pnpmpnpm is a fast, disk space efficient package manager for JavaScript and Node.js projects. It uses a content...5 APIs20.4PasqalPasqal is a French neutral-atom quantum computing company headquartered in Palaiseau, France and co-founded...8 APIs19.5SonySony Group Corporation is a Japanese multinational spanning electronics, gaming, entertainment, image senso...4 APIs18.8Apache Software FoundationThe Apache Software Foundation (ASF) is a 501(c)(3) nonprofit organization that provides open source softwa...1 API18.3GSKGSK plc (formerly GlaxoSmithKline, rebranded in May 2022) is a global biopharma headquartered in the United...18.1ChangelogChangelog is a media company and podcast network for developers covering open source and software developme...4 APIs15.4SatellogicSatellogic is an Argentine-founded, U.S.-listed (NASDAQ: SATL) vertically integrated Earth observation comp...6 APIs15.4AutomatischAutomatisch is an open source business automation tool and self-hosted alternative to Zapier that connects ...1 API14.4Refact.aiRefact.ai is an open-source, local-first AI coding assistant and autonomous software-engineering agent buil...2 APIs14.3CometComet is Perplexity's AI-native browser built on Chromium (Blink), integrating Perplexity Search and an age...13.4BoschBosch is a German multinational engineering and technology company producing automotive components, industr...5 APIs13.3
Minimal 4 Almost no public developer surface
Unrated 1 Not yet scored

What Providers Actually Declared

This feature is a canonical term. These are the free-text strings providers wrote in their own apis.yml that map onto it.

100% open source under Apache 2.0 (with separate commercial license for `highlight.io/` and `enterprise/` directories)25+ open-source inference models — Llama 3.1 8B/70B/405B, Qwen 2.5, DeepSeek V3, DeepSeek R1, Hermes 3, Mistral, Llama 3.2 Vision, Qwen2-VL300+ Open Source Projects3D Scene module with custom-layer extensibility (open-source 3d-viewer-module)AGPL-3.0 Open SourceAll Google Quantum AI open-source software is Apache 2.0 licensedApache 2.0 LicenseApache 2.0 Open Source LicenseApache 2.0 open-source licensing for pytket, qnexus, lambeq, Guppy, Selene, QermitAutoChain — open-source lightweight framework for building and testing LLM agents (1.8k+ GitHub stars)Browser-side background-removal JS library and Blender texturing plugin available as open sourceCompanion BMW Car IT open-source stack (joynr, ramses, MoCOCrW, python-dlt) underpinning connected-vehicle middlewareCore: free open-source self-managedFirely .NET SDK — official open-source C# FHIR library (de-facto reference SDK)Free open-source MCP server hostingFree open-source WordPress pluginFree, ad-free, open-source online chess server operated by a French nonprofit, funded by donationsGSK Biostatistics Open SourceHosted Flow app (React) with full source available for self-hostingHosted micro frontends: checkout, cart, my-account, microstore, identity — each open-source on GitHubKrea Realtime experience with sub-50ms image generation and an open-source Realtime 14B autoregressive video model distilled from Wan 2.1 (CC BY-NC-SA 4.0)MIT licensed, no required runtime dependencies, runs in browser, Node.js, Electron, Tauri, Deno, and React NativeMIT licensed, open source on GitHub (vercel/turborepo)MIT-licensed open sourceMIT-licensed open source codebase (composer/packagist) — operated, not designed for reuseMulti-turn agent simulations with User Simulator and Judge Agents (open-source `scenario` framework)Ocean SDK — Python open-source SDK covering dimod, dwave-system, dwave-cloud-client, hybrid, samplersOfficial OpenAPI 3.1 specification published under MIT license at github.com/conekta/openapiOn-chain programs are open-source (Apache-2.0) Anchor programs published as IDLs, npm packages, and Rust cratesOpen SourceOpen Source (BSD-3-Clause)Open Source (MIT)Open Source Cloud (OSC)Open Source EcosystemOpen Source FocusOpen Source GovernanceOpen Source InfrastructureOpen Source IoTOpen Source LicensingOpen Source MIT License

Showing 40 of 110 declared variants

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  • find_cohortsEvery scored population of providers in the catalog.
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