API Regression Tester

Record and replay JSON REST API calls for regression testing. You can save the tests to share with colleagues

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. --- 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 preserved so recipients know which token type is required — meaning no credentials are ever shared accidentally. Your colleague imports the file with one click and the session is immediately ready to run. If the imported session has the same name as an existing session, you are given the choice to overwrite the existing one or rename the import, so nothing is lost by accident. AUTOMATIC TOKEN HANDLING When you replay tests and some requests come back with a 401 or 403 status that was not in the original recording, the extension recognises that your authentication token has expired. An Update Token dialog appears automatically, shows you the type of token detected (Bearer, Basic, API key, etc.), and lets you paste a fresh token. Click Update Token & Re-run Tests and the new token is applied to all relevant requests immediately and the full test suite runs again. Your token is stored locally in Chrome only and is never transmitted to any third party. URL FILTERING Focus a recording on specific parts of your application by entering one or more URL fragments in the URL filter field, separated by commas. Only requests whose URL contains at least one of the fragments will be captured. Leave the field blank to capture all JSON responses. The filter is saved as part of each session and restored automatically when you switch sessions. PERFORMANCE MONITORING Every captured request records how long the server took to respond. During replay, if a response takes more than a configurable threshold (default 500 ms) longer than the original recording, it is flagged as SLOW. This gives you an effortless way to catch performance regressions alongside functional ones. PRIVACY API Regression Tester operates entirely within your browser. No data is sent to any external server. Recordings are stored in Chrome's local storage on your own machine. Authentication tokens entered for replay are kept locally and stripped automatically before any export. Developed by Qwentès Italia — https://qwentes.it