Comparison
Carbon vs Postman Mocks
Postman Mocks let you spin up a hosted endpoint from a Postman collection in a few clicks. If your team already lives in Postman, that low-friction start is genuinely useful. Carbon is the opposite kind of tool: it runs on your laptop, has no hosted dependency, and models state instead of returning saved example responses.
Capability by capability
Rows below are checked against Postman Mocks's public docs. Where support is "partial" we say what's actually there.
| Capability | Carbon | Postman Mocks | Notes |
|---|---|---|---|
| State persistence across requests | Postman Mocks return saved example responses; there is no server-side store. | ||
| Snapshots / rewind (state journal) | |||
| Chaos / failure injection | You can save error examples and match them via headers; no chaos presets. | ||
| Multi-format ingest (OpenAPI, GraphQL, HAR, Postman, gRPC) | Native to Postman collections; other formats via import. | ||
| Local-first (runs on your laptop) | Mocks are served from Postman-hosted infrastructure. | ||
| No hosted-service dependency | |||
| Framework glue (vitest, jest, playwright) | |||
| Drift detection vs real API |
When to pick Postman Mocks
- Your entire team already works in Postman collections.
- You need a hosted URL that a coworker or vendor can hit without any install.
- You are okay with saved example responses and do not need real state.
When to pick Carbon
- You want mocks that run offline on your laptop with no cloud dependency.
- You need the same POST-then-GET to reflect what was just written.
- You want the mock to boot inside your test process and be torn down after.
Try Carbon against your own spec.
One command turns any OpenAPI, GraphQL, HAR, Postman, or gRPC spec into a stateful local server. See how it compares to Postman Mocks on the endpoints you actually ship.