Record and replay JSON REST API calls for regression testing. You can save the tests to share with colleagues
Users
4
−2 in 30 days
Rating
5.0 / 5
unchanged in 30 days
Ratings
1
0 in 30 days
Store rank
#264K
#220K among extensions
Version
1.8.0
updated 24 Sep 2026
Users
monthly, 6 months
Latest, 16 Oct 2026:4 usersMove the mouse over the chart for any month
Ratings count
monthly, 6 months
Latest, 16 Oct 2026:1 ratingsMove the mouse over the chart for any month
The Chrome Web Store rounds user counts down to the leading digit, so the user line moves in steps. The ratings count is exact and is the better signal of real adoption.
About API Regression Tester
API Regression Tester Catch API regressions before your users do. API Regression Tester lets you record real API calls from your web application and replay them at any time — against a new build, a different environment, or after a code change — to instantly see what has broken and what has changed.
HOW IT WORKS
Using your application normally is all it takes to record a test suite. Click Start Recording, browse through the features you want to cover, then click Stop. The extension silently captures every JSON API response in the background. From that point on, you can replay those same requests with one click and get a clear pass/fail report for every endpoint.
RECORD
Click the toolbar icon to open the panel, optionally set a URL filter so only the endpoints you care about are captured, then hit Start Recording and use your application as normal. Every JSON response — including the status code, response body, and how long the server took to respond — is logged in real time. Stop recording when you are done. You will be prompted to save the recording as a named session so you can come back to it later.
You can run additional recordings on top of an existing session at any time. New captures are appended automatically, making it easy to build up a comprehensive test suite over multiple sessions.
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REPLAY AND COMPARE
Click Run Regression Tests to replay every recorded request against the live application. Results appear in the Test Results tab:
- PASS — the response body matches the recording exactly
- FAIL — one or more fields in the response have changed (the number of differences is shown)
- ERROR — the request could not be replayed (network failure, non-JSON response, etc.)
- SLOW — the server took significantly longer to respond than when the request was first recorded
Click View Diff on any failed test to see a side-by-side comparison of the recorded and replayed responses, with every changed field highlighted.
IGNORE VOLATILE FIELDS
Real-world APIs always return some fields that change on every request — timestamps, generated IDs, session tokens, pagination cursors. These would cause every test to fail even when the API is working perfectly. The Ignored Paths tab lets you exclude any field from comparison using simple dot-notation (data.updatedAt) or array notation (items[0].id). Any child field of an ignored path is automatically excluded too. You can add paths manually or directly from a diff view with one click.
SESSIONS
Sessions are the core of the workflow. Each session stores the complete set of recorded requests, all settings, and your list of ignored paths under a meaningful name you choose — for example "Checkout flow v2.4" or "Search and filter — staging".
Sessions are saved locally in Chrome and persist indefinitely.
- Switch between sessions using the dropdown at the top of the panel
- Rename or delete sessions at any time
- Any change — new captures, updated settings, fresh test results — is automatically saved back to the active session
- Starting a new session clears the current working state so you can begin fresh without losing anything previously saved
EXPORT AND SHARE
Share a session with a colleague using the Export button. A .noreg file is downloaded containing all the recorded requests and settings. Authentication tokens are automatically stripped before export — the header structure is preserve…