Hoverfly vs Mockaroo

Free and open source

From $60 per year (indicative, Silver)

Free and open source. You pay in engineering time and CI minutes.

Cheap for what it does; higher tiers raise row limits and add API quota.

Everything, self-hosted

Free for up to 1,000 rows per download and a limited number of saved schemas.

Emerging

SpectoLabs · since 2016

Established

Mockaroo LLC · since 2014

• Capture mode produces a realistic simulation from live traffic with no authoring.
• Latency injection makes it useful for performance and resilience testing too.
• Small footprint — a single Go binary.

• No code required — an analyst or tester can design a dataset themselves.
• Very large library of realistic field types including regional formats.
• Formula fields allow simple business rules between columns.

• Smaller community and slower development than WireMock.
• Proxy configuration in complex networks takes effort.
• Captured simulations need periodic refresh.

• Referential integrity across related tables is limited.
• Free-tier row limits are low for realistic volume testing.
• Data is generated on a third-party service, which needs a privacy check for schema sensitivity.

Teams needing lightweight service virtualisation against real recorded traffic.

Quickly producing a realistic dataset for a demo, a load test or a new environment.