““Autocannon is written in JavaScript for the Node.js runtime and it is CPU-bound.” — README”
You know that feeling when your local API feels fast, but you have no number to prove it under traffic? Autocannon gives you a quick way to hit an HTTP or HTTPS endpoint and read latency, requests per second, and bytes per second. It fits especially well when your service and test scripts already live in Node.js. The tradeoff is clear: you get Node-native setup, but you may hit generator CPU limits sooner than with wrk or wrk2.
Think of Autocannon like a stopwatch plus a crowd machine for one web address. You run a command such as `autocannon -c 100 -d 10 http://localhost:80`, then it opens concurrent connections and sends HTTP/1.1 requests for the chosen duration. It records latency percentiles, requests per second, bytes per second, errors, timeouts, and status code stats. If you use fixed request rates, it corrects latency data for coordinated omission unless you explicitly disable that correction. If one Node thread cannot create enough load, worker mode splits connections and request counts across worker threads.
If you benchmark Node.js HTTP services and want a fast CLI plus a Node API, this is for you. It also fits if you want quick local checks before moving to k6, Artillery, wrk, or wrk2. It is not the best first choice if you need HTTP/2 breadth or maximum load-generator efficiency from one machine.
Yes, if you work in Node.js and want quick HTTP/1.1 benchmark numbers with a mature repo behind it. The project looks stable based on v8.0.0, 8,462 stars, 96 contributors, and a 2026 last commit. Use wrk2 or another native tool when Autocannon becomes the CPU bottleneck.
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