TOOL SIGNAL / ACTIVE

Siege

Joe Dog Software

Micro-benchmark CLI Open Source Self-hosted

MAINTAINED BY · Joe Dog Software (designed and implemented by Jeffrey Fulmer)

Official site ↗ Source repo ↗
Pricing model
Free; GPL-3.0 license.
First released
2000
Latest release
4.1.7
Last verified
Answer

Siege is an open-source HTTP load testing and benchmarking utility designed to allow web developers to measure the performance of their code under load. It supports HTTP/HTTPS regression testing, internet simulation, and brute-force modes, and can simulate a configurable number of concurrent users to stress-test a web server.

About

Siege is an open-source HTTP load testing and benchmarking utility designed to allow web developers to measure the performance of their code under load. It supports HTTP/HTTPS regression testing, internet simulation, and brute-force modes, and can simulate a configurable number of concurrent users to stress-test a web server.

Best for

  • Quick HTTP or protocol micro-benchmarks from a single machine
  • Teams that prefer open-source licensing and self-hosting options
  • Groups comfortable scripting in C

Not the best fit when

  • Full multi-protocol enterprise journeys and rich business-flow reporting
  • Teams unwilling to operate generators, results storage, and scaling

Architecture and concurrency

Siege is typically driven as a CLI micro-benchmark with C. It favors single-host or simple distributed runs rather than enterprise controller grids.

Compare and alternatives

Siege alternatives 12 alternatives compared

Features

  • Supports HTTP/1.0 and 1.1 protocols
  • Supports GET and POST directives
  • Supports basic authentication, cookies, and transaction logging
  • Supports HTML parsing to harvest resources like style sheets, images, and JavaScript
  • Allows testing via configuration files (for regression and internet simulation) or command-line (for brute-force)
  • Records test duration, transactions, data transferred, response time, transaction rate, concurrency, and success status (200 OK)
  • Supports proxy server testing

Latest release

4.1.7 · 2025-01-15 (latest tagged version v4.1.7)

Latest release v4.1.7 focuses on maintenance and bug fixes, consistent with the history of the 4.x.x release branch.

Pricing

Open source; no pricing information found.

Specs

Scripting
C
Protocols
HTTPHTTPS
Operating systems
macOSLinux
Tags
cclihttp
Repo health
★ 6214 · last push 2026-08-18

Sources

SHOW SOURCES

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

Frequently asked

ANSWER-SHAPED
Who is Siege for?

Siege is best for developers who need fast HTTP or protocol micro-benchmarks from a terminal. It is open source, so teams can self-host and extend it. Vendor: Joe Dog Software. Deployment model: self-hosted. Free; GPL-3.0 license. Confirm details against the official site and a short proof-of-concept in your environment.

How does Siege differ from Vegeta?

Compared with Vegeta, scripting centers on C rather than Go. Siege lists protocols HTTP, HTTPS; Vegeta lists HTTP, HTTPS. Status is active versus active. Use the Test Rig to compare full specs side by side before a proof-of-concept. Confirm details against the official site and a short proof-of-concept in your environment.

What scripting language and concurrency model does Siege use?

Siege uses C for scripting or scenario definition. Runtime model: CLI-driven request generation with a lightweight concurrency model suited to single-host benchmarks. OS support: macOS, Linux. Protocols: HTTP, HTTPS. 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 Siege?

Siege 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; GPL-3.0 license.

What are known limitations of Siege?

Siege limitations to weigh: CLI micro-benchmarks excel at raw HTTP throughput but usually lack enterprise scenario orchestration, rich reporting, and multi-protocol suites; 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.