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Best / API testing

Best open-source API testing

The best self-hosted API-testing split in the c17.io catalog is Hoppscotch for an MIT web/desktop/self-host client (the published Postman stack), Bruno when you want that MIT git-friendly collection IDE, Scalar when the job is MIT OpenAPI references rather than a workspace, and Swagger UI when the job is an Apache-2.0 renderer. This is not Postman's every flow, monitor, or mock SKU. A public reference stays on /replace/swaggerhub (Scalar).

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Ranked picks

  1. 1

    Hoppscotch

    MIT API client — the c17 Postman path. /compare/hoppscotch-vs-bruno.

    When to pick it: A browser workspace you host.

    80,681 stars in the catalog

  2. 2

    Bruno

    MIT local API IDE with collections as files — /compare/hoppscotch-vs-bruno.

    When to pick it: Collections in git, no cloud workspace.

    47,837 stars in the catalog

  3. 3

    Scalar

    MIT OpenAPI references already on /replace/swaggerhub. Not a client workspace.

    When to pick it: A public reference, not Postman collections.

    16,316 stars in the catalog

  4. 4

    Swagger UI

    Apache-2.0 OpenAPI renderer already on /stacks/scalar-api-docs.

    When to pick it: Render one spec, not a team workspace.

    29,045 stars in the catalog

How they compare

ToolLicenseSelf-hostBest for
HoppscotchMIT LicenseEasyA browser workspace you host.
BrunoMIT LicenseEasyCollections in git, no cloud workspace.
ScalarMIT LicenseEasyA public reference, not Postman collections.
Swagger UIApache License 2.0EasyRender one spec, not a team workspace.

Related pages

FAQ

Hoppscotch or Bruno?
Hoppscotch if you want the published Postman web workspace. Bruno if collections should live in git — /compare/hoppscotch-vs-bruno.
Is this SwaggerHub?
A public OpenAPI reference stays on /replace/swaggerhub (Scalar). This page is a client workspace.
Are these free?
Hoppscotch and Bruno are MIT. Scalar is MIT. Swagger UI is Apache-2.0. You pay hosting. Template users never pay c17.
How do I deploy it?
Open /stacks/hoppscotch-api. Hoppscotch self-host if the team wants a browser. Bruno stays on the laptop.

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