About
CuTTY is a modern terminal emulator that comes with sensible defaults, but allows for extensive configuration. By integrating with other applications, rather than reimplementing their functionality, it manages to provide a flexible set of features with high performance. The supported platforms currently consist of BSD, Linux, macOS and Windows.
CuTTY is a fork of Alacritty that replaces the old OpenGL renderer with a
wgpu/vello rendering stack and a parley text pipeline. This allows CuTTY
to target modern graphics backends like Vulkan, Metal, and DirectX 12 instead
of depending on an OpenGL rendering path. Replacing the hand-rolled OpenGL
renderer with the Vello/Parley stack also cut roughly 4,000 lines of renderer
and font-handling code.
The software is considered to be at a beta level of readiness; there are a few missing features and bugs to be fixed, but it is already used by many as a daily driver.
Features
You can find an overview over the features available in CuTTY here.
Installation
CuTTY can be installed directly in a few simple ways:
-
Windows: download a release binary from the GitHub Releases page.
-
macOS: either download a release binary from the GitHub Releases page, or install it the Unix way.
-
Linux/BSD/Unix: install with:
Build and installation instructions live in INSTALL.md.
Requirements
- A graphics adapter and driver supported by
wgpu - [Windows] ConPTY support (Windows 10 version 1809 or higher)
Configuration
You can find the documentation for CuTTY's configuration in man 5 cutty, or
in the source manpage at extra/man/cutty.5.scd.
There is also a full example configuration at
extra/cutty.example.toml, and a practical
day-to-day starter config at
extra/cutty.daily.toml.
CuTTY doesn't create the config file for you, but it looks for one in the following locations:
$XDG_CONFIG_HOME/cutty/cutty.toml$XDG_CONFIG_HOME/cutty.toml$HOME/.config/cutty/cutty.toml$HOME/.cutty.toml/etc/cutty/cutty.toml
On Windows, the config file will be looked for in:
%APPDATA%\cutty\cutty.toml
CuTTY only supports TOML configuration files. Legacy YAML configs are not supported.
If you're coming from Alacritty, the main difference is fonts: CuTTY's
[font.*].family values can be CSS-style fallback lists like
"FiraMono Nerd Font, ui-monospace, monospace" instead of a single family
name.
Contributing
A guideline about contributing to CuTTY can be found in the
CONTRIBUTING.md file.
FAQ
Is it really the fastest terminal emulator?
Benchmarking terminal emulators is complicated. CuTTY uses
vtebench and kitty's performance
benchmark to quantify terminal throughput. The repo includes a single runner,
bench.sh, which launches CuTTY, Alacritty, Kitty, and Ghostty
sequentially, records both benchmark suites, and prints a final winner report.
On the local runs from March 18, 2026, CuTTY won 4 of 5 kitty benchmark
categories and all 10 measured vtebench categories.
Kitty benchmark results from March 18, 2026:
| Test | CuTTY | Alacritty | Kitty | Ghostty | Winner |
|---|---|---|---|---|---|
| CSI codes with few chars | 1.38s @ 72.4 MB/s |
1.76s @ 56.9 MB/s |
1.74s @ 57.5 MB/s |
2.36s @ 42.3 MB/s |
CuTTY |
| Images | 1.56s @ 342.1 MB/s |
2.29s @ 233.0 MB/s |
2.04s @ 261.4 MB/s |
10.35s @ 51.5 MB/s |
CuTTY |
| Long escape codes | 4.82s @ 162.7 MB/s |
6.28s @ 124.9 MB/s |
2.42s @ 324.1 MB/s |
11.02s @ 71.2 MB/s |
Kitty |
| Only ASCII chars | 1.88s @ 106.5 MB/s |
2.57s @ 77.7 MB/s |
2.07s @ 96.4 MB/s |
2.58s @ 77.5 MB/s |
CuTTY |
| Unicode chars | 1.28s @ 141.1 MB/s |
2.04s @ 88.6 MB/s |
1.46s @ 124.1 MB/s |
1.73s @ 104.3 MB/s |
CuTTY |
| Terminal | Wins |
|---|---|
| CuTTY | 4 |
| Alacritty | 0 |
| Kitty | 1 |
| Ghostty | 0 |
vtebench results from March 18, 2026:
| Test | CuTTY | Alacritty | Kitty | Ghostty | Winner |
|---|---|---|---|---|---|
| dense_cells | 8.04ms avg (90% < 8ms) |
10.23ms avg (90% < 11ms) |
17.99ms avg (90% < 18ms) |
9.57ms avg (90% < 10ms) |
CuTTY |
| medium_cells | 11.06ms avg (90% < 12ms) |
12.11ms avg (90% < 13ms) |
14.19ms avg (90% < 15ms) |
13.66ms avg (90% < 14ms) |
CuTTY |
| scrolling | 112.21ms avg (90% < 113ms) |
120.73ms avg (90% < 122ms) |
163.10ms avg (90% < 183ms) |
115.32ms avg (90% < 117ms) |
CuTTY |
| scrolling_bottom_region | 111.58ms avg (90% < 112ms) |
120.70ms avg (90% < 122ms) |
115.21ms avg (90% < 116ms) |
116.15ms avg (90% < 118ms) |
CuTTY |
| scrolling_bottom_small_region | 111.30ms avg (90% < 112ms) |
120.70ms avg (90% < 122ms) |
114.79ms avg (90% < 116ms) |
115.71ms avg (90% < 117ms) |
CuTTY |
| scrolling_fullscreen | 187.54ms avg (90% < 189ms) |
194.91ms avg (90% < 196ms) |
302.24ms avg (90% < 311ms) |
194.41ms avg (90% < 196ms) |
CuTTY |
| scrolling_top_region | 114.48ms avg (90% < 116ms) |
124.51ms avg (90% < 125ms) |
115.09ms avg (90% < 116ms) |
116.45ms avg (90% < 118ms) |
CuTTY |
| scrolling_top_small_region | 111.98ms avg (90% < 113ms) |
121.12ms avg (90% < 122ms) |
115.09ms avg (90% < 116ms) |
116.44ms avg (90% < 118ms) |
CuTTY |
| sync_medium_cells | 12.45ms avg (90% < 13ms) |
15.11ms avg (90% < 15ms) |
45.89ms avg (90% < 46ms) |
16.36ms avg (90% < 17ms) |
CuTTY |
| unicode | 7.65ms avg (90% < 8ms) |
10.60ms avg (90% < 11ms) |
14.18ms avg (90% < 9ms) |
9.03ms avg (90% < 9ms) |
CuTTY |
| Terminal | Wins |
|---|---|
| CuTTY | 10 |
| Alacritty | 0 |
| Kitty | 0 |
| Ghostty | 0 |
Those numbers are specific to that benchmark set, machine, and configuration. The best way to evaluate terminal performance is still to test your own setup. If you have found an example where this is not the case, please report a bug.
Other aspects like latency or framerate and frame consistency are more difficult to quantify. Some terminal emulators also intentionally slow down to save resources, which might be preferred by some users.
If you have doubts about CuTTY's performance or usability, the best way to quantify terminal emulators is always to test them with your specific usecases.
Why isn't feature X implemented?
CuTTY has many great features, but not every feature from every other terminal. This could be for a number of reasons, but sometimes it's just not a good fit for CuTTY. This means you won't find things like tabs or splits (which are best left to a window manager or terminal multiplexer) nor niceties like a GUI config editor.
License
CuTTY is released under the Apache License, Version 2.0.