SGR 26 — Proportional spacing (ECMA-48; ignored by every common terminal)
Defined by ECMA-48 as 'proportional spacing on' — but no common terminal emulator implements it. Document the gotcha.
Byte forms
Every common string-literal form so you can paste-and-search either direction.
\x1b[26m\033[26m\e[26mESC [ 26 m1b 5b 32 36 6dDescription
ECMA-48 §8.3.117 defines SGR 26 as `PROPORTIONAL SPACING` — a hint that the rendering device should switch from fixed-width cells to a proportional font for the following characters; `\x1b[50m` is the matching `PROPORTIONAL SPACING OFF`. **This control is effectively dead**: it was meaningful on the ANSI X3.64 / ECMA-48 print-stream targets of the 1970s–80s (typewriters, daisy-wheel printers, mainframe terminals with optional proportional firmware) but every modern terminal emulator hard-codes a monospaced grid for column math and ignores SGR 26 entirely. It is documented here so that decoders and lint tools recognise the byte sequence rather than misclassifying it — and so writers do not accidentally believe they can mix proportional and monospace text in a terminal session. If you want proportional rendering in 2026, use a non-terminal UI (web, native).
Spec citation: ECMA-48 §8.3.117 (SGR parameter 26)
Examples
printf '\033[26mproportional\033[50m back\033[0m\n' # silently ignored by xterm/kitty/iterm2/etc.import sys; sys.stdout.write('\x1b[26mproportional\x1b[50m\n')fmt.Print("\x1b[26mproportional\x1b[50m\n")process.stdout.write('\x1b[26mproportional\x1b[50m\n')printf("\x1b[26mproportional\x1b[50m\n");Terminal support
- xterm
- no
- Linux console (fbcon)
- no
- macOS Terminal.app
- no
- iTerm2
- no
- Windows Terminal
- no
- cmd.exe / ConPTY
- no
- kitty
- no
- alacritty
- no
- WezTerm
- no
- Ghostty
- no
- GNOME Terminal
- no
- Konsole
- no
- tmux
- no
- GNU screen
- no
| xterm | Linux console (fbcon) | macOS Terminal.app | iTerm2 | Windows Terminal | cmd.exe / ConPTY | kitty | alacritty | WezTerm | Ghostty | GNOME Terminal | Konsole | tmux | GNU screen |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| no | no | no | no | no | no | no | no | no | no | no | no | no | no |