Mockoon

What Mockoon is

Mockoon is a free, open-source tool for designing and running mock APIs locally. It supports OpenAPI and is intended to fit into existing applications and API design workflows. Mock behavior can use dynamic templating, rule matching, JSON databases, proxy mode, webhooks, and TLS. The tool can record real API requests and responses to generate mocks, and it supports proxying and integration testing. Its open-source version allows unlimited mock APIs and routes to run in parallel. The CLI can run mocks headlessly in automated environments such as CI, GitHub Actions, and Docker containers; mock APIs can also run in serverless environments including AWS Lambda and GCP/Firebase Functions. The desktop app stores mocks locally, works offline without an account, and reports no mock content or request data to Mockoon. Pro adds real-time team collaboration, synchronized mocks, and deployment management on private infrastructure, with self-hosting on-premises, in a private cloud, or on isolated or air-gapped networks. Team costs €10 a month, billed annually at €120/license/year, tax excluded.