Mock Service Worker alternatives: 8 open-source test data and mocking tools
Metrics as of , from the GitHub or GitLab API of each repository. Refreshed monthly.
About Mock Service Worker
Mock Service Worker is a listed test data and mocking tool: API mocking library for JavaScript that intercepts requests at the network level in browsers and Node.js.
Order: Listed tools in the same category, with tools in the same primary language (GitHub API) first, then by GitHub stars. Each line gives one fact from the tool's own documentation where it differs from what Mock Service Worker's documentation states, with its source.
8 alternatives to Mock Service Worker
@faker-js/faker: Languages for writing tests: JavaScript (browser and Node.js). source: Docs: Getting Started
Mockoon: Protocols: HTTP routes; WebSocket (ws:// and wss://). source: Docs: WebSockets
Prism: Protocols: HTTP. source: README
Testcontainers for Node.js: Languages for writing tests: Node.js. source: Docs: Testcontainers for Node.js
JSON Server: Protocols: HTTP (REST API routes for GET, POST, PUT, PATCH, DELETE). source: README
Faker: Languages for writing tests: Python (3.8 and above). source: README
Mockito: Languages for writing tests: Java. source: README
Nock: Languages for writing tests: Node.js. source: README
Repository metrics
| JSON Server | 75,7151 | 2026-03-231v1.0.0-beta.15 | 2026-03-231 | MIT | JavaScript | slow |
|---|---|---|---|---|---|---|
| Faker | 19,4051 | 2026-09-141v40.39.0 | 2026-09-151 | MIT | Python | active |
| Mock Service Worker | 18,2161 | 2026-07-081v2.15.0 | 2026-09-081 | MIT | TypeScript | active |
| @faker-js/faker | 15,4931 | 2026-08-141v10.6.0 | 2026-09-221 | MIT | TypeScript | active |
| Mockito | 15,4571 | 2026-03-111v5.23.0 | 2026-09-091 | MIT | Java | active |
| Nock | 13,1261 | 2026-07-301v14.0.17 | 2026-07-301 | MIT | JavaScript | active |
| Mockoon | 8,4171 | 2026-09-161v9.9.0 | 2026-09-201 | MIT | TypeScript | active |
| Prism | 5,0341 | 2026-07-171v5.16.0 | 2026-09-211 | Apache-2.0 | TypeScript | active |
| Testcontainers for Node.js | 2,6131 | 2026-08-041v12.1.0 | 2026-09-211 | MIT | TypeScript | active |
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