Top 11AI made for AI

Alternatives to Katalon

Katalon ranks #6 on the Top 11 The 11 Best API Testing Tools (2026). Below: the higher-ranked alternatives we’d steer you to instead, by use case.

Verified . No paid placement — see methodology.

  1. #1Postman

    9.2 / 9.4

    The most complete option for teams that need authoring, automation, and CI in one place.

    Best for: All-round team API testing · Pricing: $$ (Free tier, teams ~$14-$29/user/mo) · www.postman.com/

  2. #2Bruno

    8.8 / 9.4

    The git-first choice that keeps API tests in your repo, not a vendor cloud.

    Best for: Git-native, offline API testing · Pricing: $ (Free open source, Golden Edition one-time ~$49) · www.usebruno.com/

  3. #3Insomnia

    8.6 / 9.4

    A clean, fast client with excellent GraphQL and gRPC handling.

    Best for: Fast client with strong GraphQL support · Pricing: $$ (Free tier, paid ~$12-$25/user/mo) · insomnia.rest/

  4. #4Apidog

    8.5 / 9.4

    An all-in-one that folds design, mocking, and testing together.

    Best for: Design, mock, and test in one tool · Pricing: $$ (Free tier, paid ~$9-$25/user/mo) · apidog.com/

  5. #5SoapUI

    8.3 / 9.4

    The default when SOAP and legacy enterprise services are in scope.

    Best for: SOAP and legacy protocol testing · Pricing: $$ (Open source free; ReadyAPI upgrade is paid) · www.soapui.org/

See the full ranked list: The 11 Best API Testing Tools (2026). Or compare any two: side-by-side.