TOOL SIGNAL / ACTIVE

Fortio

Fortio project

Protocol/API Load Open Source Self-hosted

MAINTAINED BY · The Fortio project.

Official site ↗ Source repo ↗
Pricing model
Free; Apache License 2.0.
First released
2017
Latest release
1.75.2
Last verified
Answer

Fortio (Φορτίο) is a fast, small, open-source load testing tool that originated as part of the Istio project before becoming an independent project. It serves as an HTTP and gRPC load generator, an advanced echo server, and provides a web UI and REST API for result visualization.

About

Fortio (Φορτίο) is a fast, small, open-source load testing tool that originated as part of the Istio project before becoming an independent project. It serves as an HTTP and gRPC load generator, an advanced echo server, and provides a web UI and REST API for result visualization.

Best for

  • API and protocol throughput or latency campaigns
  • Teams that prefer open-source licensing and self-hosting options
  • Groups comfortable scripting in Go

Not the best fit when

  • Teams unwilling to operate generators, results storage, and scaling

Architecture and concurrency

Fortio is commonly operated as self-hosted software with scenario authoring in Go. Concurrency and distribution depend on how you size workers or injectors.

Compare and alternatives

Fortio alternatives 12 alternatives compared

Features

  • Command-line tool and embeddable Go library
  • Load testing with configurable QPS, duration, or total requests
  • Graphical representation of results (latency, throughput, percentiles)
  • Server-side debugging features (headers echo, latency/error simulation)
  • HTTP, gRPC, TCP, and UDP support
  • Result export/import via TSV index files (supports GCS, S3, peer-to-peer)

Latest release

1.75.2 · 2026-06-11

Updates build/runtime toolchain to Go 1.25.11, updates dependencies (x/net, grol, terminal, x/img) to security-fixed versions, and adjusts HTTP server configuration.

Pricing

Open-source (no cost).

Specs

Scripting
Go
Protocols
HTTPHTTPSgRPC
Operating systems
WindowsmacOSLinux
Tags
gogrpcservice-mesh
Repo health
★ 3722 · last push 2026-08-29

Sources

SHOW SOURCES

LAST VERIFIED · 2026-08-11 · GROUNDED VIA EXA · CURATED BY NAVEENKUMAR NAMACHIVAYAM

Frequently asked

ANSWER-SHAPED
Who is Fortio for?

Fortio is best for engineers focused on API and protocol-level throughput and latency. It is open source, so teams can self-host and extend it. Vendor: Fortio project. Deployment model: self-hosted. Free; Apache License 2.0. Confirm details against the official site and a short proof-of-concept in your environment.

How does Fortio differ from Artillery?

Compared with Artillery, scripting centers on Go rather than JavaScript, TypeScript. Fortio lists protocols HTTP, HTTPS, gRPC; Artillery lists HTTP, HTTPS, WebSocket, Socket.IO, MQTT. Status is active versus active. Use the Test Rig to compare full specs side by side before a proof-of-concept.

What scripting language and concurrency model does Fortio use?

Fortio uses Go for scripting or scenario definition. Runtime model: code-first scenarios where virtual users execute scripted behavior under load. OS support: Windows, macOS, Linux. Protocols: HTTP, HTTPS, gRPC. Match these to how your team already authors tests and which systems you must drive under load.

What is the cloud or enterprise path for Fortio?

Fortio is primarily self-hosted; teams typically run generators on their own machines, CI runners, or private cloud. Plan for generator capacity, network access to targets, and result storage yourself. As open source, commercial support or hosted siblings may exist separately. Check the official site. Pricing note: Free; Apache License 2.0.

What are known limitations of Fortio?

Fortio limitations to weigh: self-hosted tools require you to provision, scale, and observe load generators yourself. Status: active. Always validate against your target protocols and scale with a proof-of-concept. Confirm details against the official site and a short proof-of-concept in your environment.