mio vs tokio-util

Short answerBy steady daily use, mio is bigger: 3,332,252 real downloads a day against 2,287,578 for tokio-util (1.5x). 624 crates depend on mio and 8,109 on tokio-util. mio last shipped 21 days ago, tokio-util 15 days ago.

mio

Established

Established and steady.

624 crates depend on it; downloads don't spike on releases.

Lightweight non-blocking I/O.

tokio-util

Widely used

Widely used and steady.

8,109 crates depend on it; downloads don't spike on releases.

Additional utilities for working with Tokio.

miotokio-util · 100% = that crate's normal quiet day, so a spike to 300% is triple its usual traffic

Every number, side by side

Same window, same method	mio	tokio-util
Real downloads a day	3,332,252	2,287,578
Crates that depend on it	624	8,109
Last release	1.2.4, 21 days ago	0.7.20, 15 days ago
Trend vs the field	-6%	-3%
Release-window share	4.3%	2.5%
Downloads in the window	288,704,081	206,561,405
All-time downloads	1,170,982,578	880,960,294
Versions published	81	39
License	MIT	MIT
MSRV	1.71	1.85
First published	Nov 11, 2014	Feb 1, 2018

Which to pick

Downloads tell you what is common, not what fits. Each crate's own description above says what it is for; when the jobs differ, pick by the job.
When both fit, prefer the one more crates depend on (tokio-util, 8,109 dependents): more eyes, more answered questions, and you may already have it in your tree.
Check the release dates against your own pace: mio 21 days ago, tokio-util 15 days ago.

Also in this space

towerWidely usedTower is a library of modular and reusable components for building robust clients and servers2,342,590 a day, 5,816 dependents h2EstablishedAn HTTP/2 client and server2,290,495 a day, 296 dependents tower-httpWidely usedTower middleware and utilities for HTTP clients and servers2,044,149 a day, 3,782 dependents actix-rtEstablishedTokio-based single-threaded async runtime for the Actix ecosystem151,547 a day, 467 dependents

Compare 4 of them side by side →

Method

Real downloads = the median day with no release that day or the day before, from the crates.io API (Jul 27, 2026 to Oct 23, 2026). Raw crates.io counts include CI and bots and run high (why); the method is from our 90-day study.

Up next

Another comparison: Same method, same window. Foundational and steady vs widely used and steady.reqwest vs ureqRead it next →

Also worth your time