Modify + Reporting · $9.99/month

Test fixes on a live site before anyone ships them.

For developers, QA and agencies. Change HTML, CSS, JavaScript, headers, cookies and devices in your own browser and see the result instantly. The real site is never touched.

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Everything in ObserveUp to a year of historyCancel anytime

Find it, then test the fix

Your browser, your sandbox

Try it before you ship it.

Every change lives only in your tab. Reload the page and it's gone, or save your setup as a workspace to come back to.

Page Changes

Live HTML, CSS and JavaScript studios with an element inspector. Edit a heading, restyle a button, inject a script.

Resources

Swap or block scripts, stylesheets and images to test what a page looks like without them.

Headers & cookies

Request and response header rules, cookie edits to test caching, CSP or feature flags.

Devices & browsers

Emulate phones, tablets and custom sizes, and preview how other browsers are served.

Compare

Capture before and after, and see exactly what your change did.

HTTP/API Lab

Build and send requests with saved login profiles. Snippets are encrypted on your device.

From finding to fix

The natural next step after Observe.

Observe tells you the hero image is 1 MB, the header is missing, the button has no label. Modify lets you try the fix right there, then share the before/after.

Everything in Observe + Reporting
50 scheduled journeys
History up to a full year and 25 saved websites
Encrypted snippet storage for API work

$9.99 a month. Cancel anytime.

Includes everything in Observe + Reporting.

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