MockJet — Create Fake REST APIs Instantly, No Backend Needed

MockJet is a free hosted mock API server. Sign in with Google, create a project, and get live HTTPS mock endpoints immediately — no install, no backend, no credit card. The free plan includes 2 projects, 3 endpoints per project, 2 responses per endpoint, 100 requests / day, and a real-time request log inspector. Paid plans raise the limits and unlock team collaboration.

Yes. MockJet has a free remote MCP server. Add it to Claude Code, Claude desktop or web, Codex, Cursor, VS Code, or any MCP client. Sign in to MockJet once with OAuth — no API keys — and your AI assistant can create and manage mock APIs in your account just by asking. See the MockJet MCP server setup guide for instructions.

No. MockJet runs entirely in your browser. Sign in with Google, create a project, and you get a live URL immediately — no npm, no Docker, no config files.

Yes. Import any Postman Collection v2.1 file and MockJet will scaffold all your endpoints automatically, including nested folders and saved example responses. You can also export back to Postman anytime.

Yes. MockJet runs a remote MCP (Model Context Protocol) server. Add the MockJet MCP URL to Claude Code, Claude desktop or web, Codex, Cursor, VS Code, or any assistant that supports remote MCP servers, sign in to MockJet once, and click Allow. Then describe the API you need, for example "create POST /login that returns a token, and a 401 when the password is wrong", and the assistant creates the project, endpoints, and conditional responses for you. The mocks are live HTTPS URLs immediately, and the assistant can also read request logs to help debug your integration.

The MockJet MCP server exposes MockJet's mock API tools (list and create projects, create and update endpoints, add and activate responses with match conditions, and read request logs) over the Model Context Protocol, so AI coding assistants can use them directly. No API key is needed: your AI app connects with OAuth, you approve it in your browser, and it acts only on projects you can access. You can see every connected app and disconnect any of them at any time from the Connect AI page in your dashboard.

Sequential mode cycles through your response list in order. The first request gets response 1, the second gets response 2, and so on. When it reaches the end, it loops back. This is useful for testing pagination, state transitions, or retry logic.

Yes. Invite teammates by email and assign them a role: Editor (can create and modify endpoints) or Viewer (read-only access). Owners have full control including deleting the project.

MockJet is designed for development and testing — mocking dependencies during frontend development, integration testing, demos, and CI environments. It's not intended as a replacement for a production API server.

MockJet is a free online mock API server — a tool that lets you create fake REST API endpoints with configurable HTTP responses, status codes, latency, and headers. You use it to simulate a real backend API during development or testing, without writing any server code. Your mock endpoints are live HTTPS URLs accessible from anywhere the moment you create them.

Mockoon is a desktop application — it runs a local mock server on your machine, so your fake API endpoints are only accessible at localhost. MockJet is fully cloud-hosted: your mock endpoints are live public HTTPS URLs accessible from any device, teammate, or CI pipeline with no download, no local server, and no ngrok tunnel required. MockJet also adds Postman Collection import on the free plan, with team collaboration (owner/editor/viewer roles) available on paid plans.

Yes. Like Beeceptor, MockJet gives you a hosted HTTPS mock endpoint with real-time request logs. MockJet additionally offers sequential and random response modes (rotate through a list of responses per endpoint), per-response latency simulation, and Postman Collection v2.1 import and export — available on the free plan. Team collaboration with owner/editor/viewer roles is available on paid plans.

Sign in to MockJet with Google (free, no credit card), create a project, and add your first endpoint — choose the HTTP method, set the URL path, configure the JSON response body and status code, and your live HTTPS mock API URL is ready in under 60 seconds. No npm, no Docker, no config files. You can also import an existing Postman Collection to scaffold an entire project in one click.

Yes, and it removes all the setup. json-server requires Node.js, a local npm install, and only exposes a localhost URL — which means your mobile device, a teammate's machine, or a CI pipeline can't reach it without extra tooling like ngrok. MockJet is fully hosted, so your mock REST API endpoint is a public HTTPS URL from the start. It also adds sequential/random response modes, latency simulation, and team sharing that json-server doesn't support.

Yes — this is called conditional response routing. You attach match rules to any response. A rule has three parts: where to look (body, header, or query), what field to check, and which operator to use.

Available operators: eq, neq, contains, not_contains, regex, exists, not_exists.

Examples:

• Return HTTP 401 when header.Authorization not_exists
• Return admin data when body.role eq admin
• Return HTTP 422 when body.email not_exists
• Return an empty list when query.filter eq none

Rules are evaluated in sort order — the first response whose rules all pass is returned. Responses with no rules are catch-alls, handled by the endpoint's fixed/random/sequential mode. No code, no backend.

MockJet supports dynamic response templating. Place {{variable}} tokens anywhere in your response body — they resolve to fresh values on every request.

Available tokens:

• {{uuid}} — UUID v4
• {{timestamp}} — ISO 8601 UTC timestamp
• {{timestamp_ms}} — Unix milliseconds
• {{randomBool}} — true or false
• {{randomInt(1,1000)}} — integer in range
• {{randomFloat(0.5,99.9,2)}} — decimal with precision
• {{randomName}} — full name
• {{randomEmail}} — email address
• {{randomPhone}} — phone number
• {{randomItem(pending,processing,complete)}} — pick from list

Example: {"id":"{{uuid}}","name":"{{randomName}}","created":"{{timestamp}}"} returns unique realistic data on every hit.

MockJet gives you two approaches:

1. Conditional routing — add a rule to any response so the error only fires when the request matches. For example: return HTTP 401 when header.Authorization not_exists, return HTTP 429 when body.qty regex ^[5-9]\d{2,}, or return HTTP 500 for a specific endpoint path. This lets you test your error-handling UI against a real HTTPS endpoint with no backend.

2. Static error response — just create a response with status code 400, 401, 403, 404, 422, 429, 500, 502, or 503 and set it as the active response. Switch between happy-path and error-path with one click in the dashboard.

You can also enable timeout mode to make the endpoint hang for a configurable delay and then return a 504 Gateway Timeout — useful for testing loading states and request cancellation.

Yes. Using conditional response routing, you can make a single endpoint behave exactly like an auth-aware API. A common setup looks like this:

• Response 1 — 401 Unauthorized: rule header.Authorization not_exists
• Response 2 — 403 Forbidden: rule body.role eq viewer
• Response 3 — 200 Admin data: rule body.role eq admin
• Response 4 — 200 Default: no rules (catch-all)

MockJet evaluates rules in sort order — the first match wins. Your frontend team can test the full auth flow — missing token, insufficient permissions, valid admin token — against a live HTTPS URL from day one. No backend, no token issuance, no staging environment.

Yes. MockJet includes a built-in webhook inspector. You get a unique HTTPS URL that accepts any HTTP request from any sender. Open the inspector page and incoming requests stream in real-time — showing the full method, path, headers, body, sender IP address, and geo-location (country, city, ISP).

Request history is persisted in your browser's localStorage so you never lose it on page reload. You can:

• Copy any incoming request as a curl command
• Add notes to individual requests
• Filter by method, IP, path, or body content
• Configure the response the URL returns to the caller (status code, JSON body, delay)

No install, no linking required — just create a webhook, copy the URL, and start sending requests.

Yes. Like webhook.site and RequestBin, MockJet gives you a unique HTTPS URL that captures any incoming HTTP webhook request and displays full headers, body, method, and sender IP in real-time.

MockJet adds on top:

• Live SSE streaming — requests appear instantly, no polling or page reload
• localStorage history — survives navigation; requests buffered in DB while your browser is closed
• Multi-tab sync — all open tabs update simultaneously via BroadcastChannel
• Geo-IP lookup — country, city, and ISP for every request
• Configurable response — set the status code, JSON body, and delay returned to the sender

All features are available on the free plan with no install required.

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