What it does
WebPageTest runs synthetic browser tests against a web page and reports how its resources load under a selected configuration. Its current documentation describes Instant Tests in the Catchpoint Portal: enter a page URL, choose a device and connection, select a test location, and run the test. Results include a summary, a load-progress filmstrip, and a request waterfall that can help locate costly parts of the page load.
Build a repeatable lab test
The current Instant Test guide starts in the Catchpoint Portal. Open Instant Tests, choose New Test, enter the page URL, select a device and connection combination, and choose a location node before running the test. This gives a team a repeatable way to compare a page under defined browser and network conditions; it is a synthetic measurement, not a recording of every real visitor's experience.
When the run completes, the summary shows the tested URL and its device, browser, connection, and location settings. The filmstrip presents screenshots across the loading process, while the Waterfall tab lays out individual requests on a timeline. Use the waterfall to investigate which assets contribute to a slow load, then change the application and run the same configuration again.
The official FAQ describes a free Starter plan and a paid Pro subscription. Pro adds features such as bulk testing, premium locations, experiments, private tests, and the WebPageTest API. Exact current paid rates were not established in accessible pricing text, so no amount is quoted.
The public WebPageTest landing page returned an access-denied response during research. This guide therefore describes the documented Catchpoint Portal workflow rather than asserting that its public-site screens are identical.
Strengths
- Tests can be configured by device, browser, connection, and location to compare controlled page-load conditions.
- Filmstrip and request-waterfall views show when page elements appear and how individual requests contribute to loading.
- The free Starter plan supports manual tests, while Pro adds API, bulk, private-test, and premium-location capabilities.
Watch out for
- Advanced features such as the API, bulk tests, private tests, and premium locations are part of the paid Pro plan.
- A synthetic test represents its selected device, browser, connection, and location rather than every visitor's real-world experience.
Best for
- Diagnosing page-load delays with request-level performance evidence
- Comparing page behavior across selected browsers, devices, and test locations
- Adding repeatable website performance checks to a team's workflow through the Pro API
Sources
- Running Instant Tests (Oct 25, 2026)
- Interpreting Instant Test Results (Oct 25, 2026)
- WebPageTest FAQs (Oct 25, 2026)