Fortio vs Vegeta

Fortio is a free, open-source Go project for HTTP and gRPC load testing. It combines a load-testing library, command-line tool, echo server, and web interface, with API, Linux, macOS, self-hosted, web, and Windows platforms. A run can target a specified queries-per-second rate or maximum speed, and can stop after a duration, a fixed call count, or interruption. Fortio records latency histograms and percentiles such as p99. Its server offers a web UI and REST API for starting tests and viewing latency and comparison graphs. Additional server functions include request echo, probabilistic latency or error injection, TCP echo and proxy, HTTP fan-out proxy, and gRPC echo and health. Go applications can embed Fortio or use its log, stats, and fhttp components separately. Fortiotel adds OpenTelemetry hooks. Fortio Proxy can provide HTTPS with automatic certificates and multiplex gRPC and HTTP behind one port. Installation options include Docker, Go, binaries, Homebrew, and a Windows ZIP.

Vegeta is a free, open-source HTTP load-testing tool and Go library that sends requests at a constant rate. Its command-line interface is built for UNIX-style composition, while the library offers use from Go programs. The project states that its load measurements avoid coordinated omission and that distributed testing is supported. Reports can be written as text, JSON, histograms, or HDR plots, and results can also be encoded as CSV, Gob, or JSON. The attack command can expose an optional Prometheus exporter. HTTP/2 works when supported by the server, including HTTP/2 over TCP without TLS. TLS options include client certificates and keys, custom root certificates, and ignoring invalid server certificates. The documented request timeout defaults to 30 seconds, with zero disabling timeouts. Prebuilt binaries, package-manager installs, distribution packages, and source builds are documented for Linux, macOS, Windows, API use, and self-hosting. The repository uses the MIT license.