explaingit

tsenart/vegeta

★ 25,033GoAudience · developerComplexity · 2/5MaintainedLicenseSetup · easy

TLDR

A command-line load testing tool that fires high-volume HTTP requests at web servers to measure performance, response times, and reliability under stress.

Mindmap

mindmap
  root((vegeta))
    What it does
      Fires HTTP requests
      Measures response times
      Generates reports
      Creates HTML plots
    How to use
      Set target URL
      Choose request rate
      Run for duration
      View results
    Use cases
      Stress test APIs
      Benchmark infrastructure
      Validate SLAs
      Find breaking points
    Tech stack
      Go language
      HTTP/2 support
      TLS certificates
    Features
      CLI tool
      Go library
      Distributed testing
      Custom headers

Things people build with this

USE CASE 1

Stress-test a new API before launching to production to ensure it handles expected traffic.

USE CASE 2

Benchmark how infrastructure changes (new servers, caching layer) affect response times and throughput.

USE CASE 3

Validate that your service meets performance SLAs by simulating real-world load patterns.

USE CASE 4

Identify the breaking point of a web service by gradually increasing request rates until it fails.

Tech stack

GoHTTP/2TLS

Getting it running

Difficulty · easy Time to first run · 5min
Use freely for any purpose, including commercial use, as long as you keep the copyright notice.

In plain English

Vegeta is a load testing tool for HTTP services, meaning it hammers a web server with a high volume of requests to see how it holds up under pressure. The name is a Dragon Ball Z reference ("It's over 9000!"), hinting at its ability to push extremely high request rates. It solves the problem of not knowing whether your API or website will stay fast and reliable when many users hit it at the same time. You give Vegeta a target URL and a request rate (say, 50 requests per second), and it fires traffic at that endpoint for a set duration. Afterward, it generates detailed reports: response times, success rates, latency percentiles, and more. You can also pipe the results into a visual HTML plot. It's deliberately designed to avoid "coordinated omission," a subtle measurement flaw where slow responses skew results by hiding how bad the worst cases really are. Vegeta works both as a command-line tool and as a Go library you can embed in your own code. Installation is straightforward via Homebrew on macOS, pacman on Arch Linux, or a pre-compiled binary. It supports HTTP/2, TLS certificates, custom headers, and distributed load testing across multiple machines. You'd reach for Vegeta when stress-testing a new API before launch, benchmarking infrastructure changes, or validating that your service meets a performance SLA (service level agreement, a target like "respond in under 200ms"). Built in Go.

Copy-paste prompts

Prompt 1
How do I use vegeta to load test my API at 100 requests per second for 5 minutes and get a latency report?
Prompt 2
Show me how to set up distributed load testing with vegeta across multiple machines to test my service.
Prompt 3
How do I create an HTML plot of vegeta load test results to visualize response times and success rates?
Prompt 4
What's the vegeta command to test an endpoint with custom headers and TLS certificate validation?
Prompt 5
How do I use vegeta as a Go library to programmatically run load tests and check if my service meets SLA targets?
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Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.