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NO_COLOR env variable

Category: device · Baseline: modern · Specification ↗

$NO_COLOR
The NO_COLOR environment variable is a community standard documented at no-color.org. When it is set to any non-empty value, programs that emit ANSI color escapes should suppress them and produce uncolored output. The convention was proposed by Jason Stafford in 2017 and has since been adopted by more than 300 applications, libraries, and language standard libraries. Unlike the other environment variables on this page, NO_COLOR is set by the user (or a wrapper script) rather than the terminal — but it interacts with the same self-identification machinery, since applications often consult NO_COLOR alongside COLORTERM and TERM when deciding how much color to emit.
How this is testedmanual
Manual verification required — no automated probe available.

The same probe runs against headless backends (via Termless) and real terminal apps (via a daemon launched in each terminal). This lets us distinguish parser correctness from rendering correctness.

Supported by 0 of 14 backends (0%)

Terminal Applications

TerminalVersionSupportNotes
iTerm23.6.9? unknown
Ghostty1.3.1? unknown
Terminal.app2.15? unknown
Kitty0.46.2? unknown
VS Code1.113.0? unknown
Warp0.2026.03.18.08.24.03? unknown
Cursor2.6.21? unknown

Headless Backends

Parser correctness only — a means the parser accepts the sequence.

BackendVersionSupportNotes
Alacritty0.26.0? unknown
vt100.js0.2.1? unknown
vterm0.2.0? unknown
WezTerm0.1.0-fork.5? unknown
xterm.js5.5.0? unknown