Mock Studio: HTTP API Mock

Tracking since Apr 1, 2026.

Changelog

• Apr 1, 2026
  description

  Mock Studio is a strong API mocking and simulation tool built right into Chrome DevTools. You can create realistic mock APIs, test complex user flows, generate dynamic responses, and simulate real backend behavior, all within your browser.
  
  This tool is great for frontend developers, QA engineers, designers, and product teams.
  
  Key features:
  
  1. Mock REST API Instantly
  
  Create mock endpoints with custom responses, headers, status codes, and delays. Override real network requests without changing backend code.
  
  2. Mock Scenarios (Full User Journeys)
  
  Group multiple endpoints into a single scenario. Simulate login flows, checkout errors, pagination states, expired tokens, or failure chains with one click.
  
  3. Live Request Logs
  
  See network activity in real time inside DevTools. Turn any request into a mock instantly.
  
  4. Variants & Error Simulation
  
  Easily test:
  	•	success
  	•	validation errors
  	•	401/403 auth failures
  	•	empty states
  	•	timeouts
  	•	random failures
  	•	slow backend responses
  
  5. AI-Assisted Mock Generation (Pro), or use your own AI Credentials (BYOK - Bring Your Own Keys)
  
  Generate full mock collections, variants, and scenarios from:
  	•	API requests
  	•	OpenAPI/Swagger specs
  	•	Sample JSON
  	•	Real logs
  
  6. Local-First & Private
  
  All data is stored locally via IndexedDB. Nothing is uploaded. Ever. It’s ideal for enterprise privacy needs.
  
  Change Logs: https://mockstudio.app/changelog

  Mock Studio is a strong API mocking and simulation tool built right into Chrome DevTools. You can create realistic mock APIs, test complex user flows, generate dynamic responses, and simulate real backend behavior, all within your browser.
  
  This tool is great for frontend developers, QA engineers, designers, and product teams.
  
  Key features:
  
  1. Mock REST API Instantly
  
  Create mock endpoints with custom responses, headers, status codes, and delays. Override real network requests without changing backend code.
  
  2. Mock Scenarios (Full User Journeys)
  
  Group multiple endpoints into a single scenario. Simulate login flows, checkout errors, pagination states, expired tokens, or failure chains with one click.
  
  3. Live Request Logs
  
  See network activity in real time inside DevTools. Turn any request into a mock instantly.
  
  4. Variants & Error Simulation
  
  Easily test:
      •    success
      •    validation errors
      •    401/403 auth failures
      •    empty states
      •    timeouts
      •    random failures
      •    slow backend responses
  
  5. AI-Assisted Mock Generation (Pro), or use your own AI Credentials (BYOK - Bring Your Own Keys)
  
  Generate full mock collections, variants, and scenarios from:
      •    API requests
      •    OpenAPI/Swagger specs
      •    Sample JSON
      •    Real logs
  
  6. Local-First & Privacy
  
  All mock configurations, scenarios, and response data are stored locally in your browser's IndexedDB. This data never leaves your device and is never transmitted to any server.
  
  If you sign in with Google (optional, required only for Pro features), we collect your email address, display name, and profile picture for authentication and subscription management. A session token is stored locally on your device and sent only to our server to verify your subscription status.
  
  Mock Studio does NOT collect browsing history, network request payloads, keystrokes, location data, financial information, or usage telemetry. We do not sell or share your data with third parties for advertising.
  
  Full Privacy Policy: https://mockstudio.app/privacy
  Change Logs: https://mockstudio.app/changelog

Permissions & access

Permissions

declarativeNetRequeststorageunlimitedStorage

Host access

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Screenshots

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