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by rakyll

rakyll /hey

HTTP load generator, ApacheBench (ab) replacement, formerly known as rakyll/boom

8.7K Stars 658 Forks Last release: 6 months ago (v0.1.3) Apache License 2.0 282 Commits 4 Releases

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hey is a tiny program that sends some load to a web application.

hey was originally called boom and was influenced from Tarek Ziade's tool at tarekziade/boom. Using the same name was a mistake as it resulted in cases where binary name conflicts created confusion. To preserve the name for its original owner, we renamed this project to hey.


Package Managers

macOS: - Homebrew users can use

brew install hey



hey runs provided number of requests in the provided concurrency level and prints stats.

It also supports HTTP2 endpoints.

Usage: hey [options...] <url>

  -n Number of requests to run. Default is 200.
  -c Number of workers to run concurrently. Total number of requests cannot
      be smaller than the concurrency level. Default is 50.
  -q Rate limit, in queries per second (QPS) per worker. Default is no rate limit.
  -z Duration of application to send requests. When duration is reached,
      application stops and exits. If duration is specified, n is ignored.
      Examples: -z 10s -z 3m.
  -o Output type. If none provided, a summary is printed.
      "csv" is the only supported alternative. Dumps the response
      metrics in comma-separated values format.

  -m HTTP method, one of GET, POST, PUT, DELETE, HEAD, OPTIONS.
  -H Custom HTTP header. You can specify as many as needed by repeating the flag.
      For example, -H "Accept: text/html" -H "Content-Type: application/xml" .
  -t Timeout for each request in seconds. Default is 20, use 0 for infinite.
  -A HTTP Accept header.
  -d HTTP request body.
  -D HTTP request body from file. For example, /home/user/file.txt or ./file.txt.
  -T Content-type, defaults to "text/html".
  -a Basic authentication, username:password.
  -x HTTP Proxy address as host:port.
  -h2 Enable HTTP/2.

  -host HTTP Host header.

  -disable-compression Disable compression.
  -disable-keepalive Disable keep-alive, prevents re-use of TCP
                        connections between different HTTP requests.
  -disable-redirects Disable following of HTTP redirects
  -cpus Number of used cpu cores.
                        (default for current machine is 8 cores)

Previously known as

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