Mock Dream is a free Chrome extension that intercepts fetch and XHR requests in any tab and replies with mock JSON, headers and status codes you define visually — no server, no sign-up.

How is it different from Mockoon, Beeceptor or Requestly?

Mockoon and Beeceptor run a local or cloud mock server. Mock Dream runs entirely inside the Chrome popup with zero servers and zero accounts. It is more focused than Requestly: rules, traffic console, JSON formatter, per-rule CORS and themes — that's it.

Does Mock Dream collect any data?

No. Zero telemetry, zero tracking, zero accounts. Every rule and request lives in chrome.storage.local on your machine.

Can I mock fetch and XMLHttpRequest at the same time?

Yes. Mock Dream patches both window.fetch and XMLHttpRequest from a single rule, so the same mock works for axios, native fetch, jQuery.ajax and legacy XHR code.

Mock Dream vs Postman

API client + mock server · free Chrome alternative

Postman is the de-facto API client. Its mock-server feature spins up a cloud endpoint from your collection.

Where Postman wins

Complete API workflow: design, test, document, monitor, mock.

Where Mock Dream wins

If you only need to mock responses for a frontend you're already debugging, Mock Dream is one popup vs an entire app + cloud account.

Side-by-side

Feature	Postman	Mock Dream
Pricing	Free tier, $14+/mo paid	Free forever
Sign-up required	Required	Never
Runs a server	Yes — cloud mock	No — runs in your tab
Mocks fetch + XHR	Both (via cloud URL)	Both, from one rule
Per-rule CORS	Cloud config	One toggle
Live traffic console	Postman console	Built-in, filterable
Themes	1 (default)	6 manga themes
Install size	Desktop or web app	<300 KB extension

FAQ

Is Mock Dream really a free Postman alternative?: Yes. Mock Dream is MIT-licensed, has zero paid tier, no telemetry, and stores everything locally in chrome.storage.local.
Can it replace Postman for my workflow?: If your job is "intercept fetch/XHR in a browser tab and return mock JSON", yes. If you need complete api workflow: design, test, document, monitor, mock., keep Postman — Mock Dream and Postman can coexist on the same machine.
Does Mock Dream work on Edge, Brave, Opera or Arc?: Yes — any Chromium browser running Manifest V3 (Chrome 116+).

Try Mock Dream — no install, no sign-up

popup runs the same engine as the extension

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