FetchLab: CORS Tester

FetchLab is a simple test browser for developers and curious users who want to see how web requests behave in two different modes.

TWO NETWORK MODES
- Browser network (default): web pages send their own requests, exactly like a normal browser.
- App network: the app sends the page's fetch() requests instead. In this mode, browser cross-site (CORS) restrictions do not apply, so you can see what a request returns without those limits.

Switch between the two at any time with the toggle at the top of the screen. App network always starts OFF when you open the app, and you must confirm before turning it on.

WHO IT IS FOR
- Web and mobile developers testing API endpoints and CORS behavior
- Students learning how browsers and networks work
- Anyone comparing how a page behaves with and without cross-site restrictions

BUILT TO BE SIMPLE AND LIMITED
- No accounts and no login support
- Cookies are turned off, so sessions are not saved
- Downloads are disabled
- File uploads are disabled
- Requests to private or local network addresses are blocked in the released app
- No ads and no analytics

IMPORTANT
- Do not enter passwords or personal information into any website. This app is not designed for logging in.
- Only use App network mode on websites you trust.
- Do not use FetchLab for banking, email, or social media.
- FetchLab is a testing tool, not a replacement for your everyday browser.

BASIC BROWSER FEATURES
Address bar with search, back, forward, reload, and a page loading indicator.

The app itself does not collect or sell your personal data. Please read our privacy policy for details.

Contact: [email protected]