Based on our record, MockLab seems to be more popular. It has been mentiond 1 time since March 2021. We are tracking product recommendations and mentions on Reddit, HackerNews and some other platforms. They can help you identify which product is more popular and what people think of it.
Both of these tools you would have to run yourself. If you wanted a hosted solution you can use for example Mocklab which is based on Wiremock. - Source: Reddit / 2 months ago
WireMock - WireMock - a web service test double for all occasions.
Mockable - Quickly define some REST or SOAP endpoints and have them return json/xml (dummy) data.
Beeceptor - Build a mock Rest API endpoint in seconds.
Postman - The Collaboration Platform for API Development
MockServer - Easy mocking of any system you integrate with via HTTP or HTTPS.
RoboHydra - RoboHydra is a web server designed to help you test any kind of HTTP client: