A Rust crate to convert bytes into human-readable values
chore: release v0.4.3
chore: update author, homepage & repo
feat(bin): drop dependency on atty



You can also use your local clone with git send-email.


A Rust crate & cli to convert bytes into human-readable values.

License Latest version Build status

It can return either KiB/MiB/GiB/TiB or KB/MB/GB/TB by disabling the si-units feature.

1 KiB = 1024 B, 1 KB = 1000 B

It supports from 0 bytes to several yottabytes (I cannot tell how many because I have to use u128s to fit a single YB)


#As a CLI

  • (Optional) Install Just
  • Build:
    • With just: just build-binary
    • Plain cargo: cargo build --release --features 'build-binary fast' --bin hb
  • Copy target/release/hb to somewhere in your $PATH
  • Run hb <bytes> or echo <bytes> | hb

#As a library

Add to your Cargo.toml:

human_bytes = "0.4"
# or, to disable the SI Units:
human_bytes = { version = "0.4", default-features = false }

And then

use human_bytes::human_bytes;

assert_eq!(human_bytes(563_200_u32), "550 KiB".to_string());
// or
assert_eq!(human_bytes(563_200_u64 as f64), "550 KiB".to_string());
// ________________________________/
// |
// | Needed only when you're using `u64` values,
// | because `f64` doesn't implement `std::convert::From<u64>`

// With the `si-units` feature disabled:
assert_eq!(human_bytes(550_000_u32), "550 KB".to_string());

The crate is dependency-free, but you can boost the speed by enabling the fast feature, which switches from using std::format! to ryu to convert floats to strings.

human_bytes = { version = "0.4", features = ["fast"] }


The code is based on a PHP function I found here.

It is useful because you don't have to provide a prefix, it does it on its own. It'll always return 1 MiB instead of 1024 KiB

It has some tests I wrote to check that the conversion is correct, and it returns decimals (e.g. 16.5 GiB)


Check the CHANGELOG.md


BSD 2-clause (c) 2020-2022 Namkhai B.