Feature checklists rarely decide anything. What decides it is the pricing metric, who has to write the tests, and which limitation you can live with.
Entry price
Free tier available
Free tierFree tier available
Free tierWhat drives the bill
The metric that actually scales your invoice.
Libraries are free. PactFlow, the hosted broker with governance features, is a paid SaaS priced per contract/service.
Open source core; Karate Labs sells a commercial IDE and enterprise support separately.
Free tier
The Pact libraries and the open-source Pact Broker are free.
The open-source framework is complete and free.
Open source
MIT
MIT
Self-hostable
No-code authoring
Languages
Platforms
Fits teams
Adoption
Widely used
SmartBear / Pact Foundation · since 2013
Widely used
Karate Labs · since 2017
Strengths
Limitations
Best for
Microservice organisations where teams deploy independently and integration environments are a bottleneck.
Teams wanting API testing and mocking in one tool, including non-Java testers.
All of these integrate with: Jenkins.
Pricing last reviewed August 2026 and is indicative only — confirm on each vendor’s own page.