Skip to content
A rate limiter for node.js streams.
Branch: master
Clone or download
Fetching latest commit…
Cannot retrieve the latest commit at this time.
Type Name Latest commit message Commit time
Failed to load latest commit information.
src throttle.js: add missing semicolon Oct 24, 2013
.gitignore Initial commit Oct 21, 2013
AUTHORS Initial commit Oct 21, 2013
LICENSE Initial commit Oct 21, 2013 Document the throttleproxy.js utility in README Apr 4, 2014


A rate limiter for Node.js streams.

API usage

This module exports two classes, Throttle and ThrottleGroup.

Throttle creates a single throttled stream, based on stream.Transform. It accepts an opts parameter with the following keys:

  • opts.rate is the throttling rate, in bytes per second.
  • opts.chunksize (optional) is the maximum chunk size into which larger writes are decomposed; the default is opts.rate/10.

The opts object may also contain options to be passed to the stream.Transform constructor.

For example, the following code throttles stdin to stdout at 10 bytes per second:

process.stdin.pipe(new Throttle({rate: 10})).pipe(process.stdout)

ThrottleGroup allows the creation of a group of streams whose aggregate bandwidth is throttled. The constructor accepts the same opts argument as for Throttle. Call throttle on a ThrottleGroup object to create a new throttled stream belonging to the group.

For example, the following code creates two HTTP connections to, and throttles their aggregate (downstream) bandwidth to 10 KB/s:

var addr = { host: '', port: 80 };
var tg = new ThrottleGroup({rate: 10240});

var conn1 = net.createConnection(addr),
    conn2 = net.createConnection(addr);

var thr1 = conn1.pipe(tg.throttle()),
    thr2 = conn2.pipe(tg.throttle());

// Reads from thr1 and thr2 are throttled to 10 KB/s in aggregate

Command line usage

This package installs a throttleproxy binary which implements a command-line utility for throttling connections. Run throttleproxy -h for instructions.


Feel free to open an issue or send a pull request.


BSD-style. See the LICENSE file.


Copyright © 2013 Tiago Quelhas. Contact me at <>.

You can’t perform that action at this time.