CSI SGR — Select Graphic Rendition (colors & text attributes)

SGR (final byte 'm') sets character rendition: bold, italic, underline, reverse, and foreground/background color. Written CSI Ps ; Ps ... m, where each Ps is a numeric code. Code 0 resets all attributes. 30–37/40–47 select the 8 base fg/bg colors, 90–97/100–107 their bright variants, and 38/48 with a 5;n (256-color) or 2;r;g;b (truecolor) sub-parameter select indexed or 24-bit color.

aka: SGR · Select Graphic Rendition · ANSI color codes · ANSI escape colors · CSI m · ESC [ m · text attributes

parameters / subcommands

id	name	bytes (ST)	meaning
0	Reset / Normal	\x1b[0m	Turn off all attributes; restore default foreground and background. 'CSI m' (empty parameter) is equivalent.
1	Bold / increased intensity	\x1b[1m	Bold or increased intensity. Reset by 22.
3	Italic	\x1b[3m	Italicized. Reset by 23. (Code 2 = faint, code 5 = blink are also defined but less universally supported.)
4	Underline	\x1b[4m	Underlined. Reset by 24. (xterm/kitty also support 4:2 double, 4:3 curly via the colon sub-parameter form.)
7	Reverse / inverse video	\x1b[7m	Swap foreground and background. Reset by 27.
22	Normal intensity	\x1b[22m	Neither bold nor faint; turns off 1 and 2.
23	Not italic	\x1b[23m	Turns off italic (3).
24	Not underlined	\x1b[24m	Turns off underline (4).
27	Not reversed	\x1b[27m	Turns off reverse/inverse video (7).
30-37	Foreground color (8-color)	\x1b[31m	Set foreground to one of the 8 base colors: 30 black, 31 red, 32 green, 33 yellow, 34 blue, 35 magenta, 36 cyan, 37 white.
38	Extended foreground color	\x1b[38;5;0m	Select foreground from the 256-color palette (38;5;n) or a 24-bit direct color (38;2;r;g;b). See sub-parameters.
39	Default foreground color	\x1b[39m	Reset foreground to the terminal's default.
40-47	Background color (8-color)	\x1b[41m	Set background to one of the 8 base colors: 40 black, 41 red, 42 green, 43 yellow, 44 blue, 45 magenta, 46 cyan, 47 white.
48	Extended background color	\x1b[48;5;0m	Select background from the 256-color palette (48;5;n) or a 24-bit direct color (48;2;r;g;b). Mirrors 38.
49	Default background color	\x1b[49m	Reset background to the terminal's default.
90-97	Bright foreground color	\x1b[91m	Set foreground to one of the 8 bright (aixterm) colors: 90 bright black (gray), 91 bright red, 92 bright green, 93 bright yellow, 94 bright blue, 95 bright magenta, 96 bright cyan, 97 bright white.
100-107	Bright background color	\x1b[101m	Set background to one of the 8 bright (aixterm) colors: 100 bright black through 107 bright white.

gotchas

Always reset with 'CSI 0 m' (\x1b[0m) when done; leaving attributes set bleeds color into subsequent output and the next prompt.
Multiple codes can be combined in one sequence with ';' separators, e.g. \x1b[1;31;44m = bold + red fg + blue bg.
38/48 with the 2;r;g;b (truecolor) form: ISO 8613-6 / ITU T.416 actually specify a COLON-delimited form (38:2::r:g:b) with a color-space-id slot; xterm and most terminals accept the simpler SEMICOLON form (38;2;r;g;b). Some strict parsers only accept one. The colon form is unambiguous because it cannot be confused with separate SGR parameters.
Bright colors via 90–97/100–107 (aixterm) are NOT in ECMA-48; some old/limited terminals only reach bright colors via the bold attribute (1) plus 30–37. Prefer 90–97 where supported.
Code 1 (bold) historically also brightened the foreground color on many terminals; whether 'bold' changes weight, brightness, or both is terminal- and theme-dependent.
An empty parameter list ('CSI m', i.e. \x1b[m) means reset (0), but relying on it is less portable than writing \x1b[0m explicitly.

provenance

source: https://invisible-island.net/xterm/ctlseqs/ctlseqs.html
version: xterm ctlseqs, patch #410, 2026/04/19
retrieved: 2026-05-29 · updated: 2026-05-29T00:00:00Z

per-fact attribution:

ext.frame — https://invisible-island.net/xterm/ctlseqs/ctlseqs.html CSI = ESC [ (0x1B 0x5B), 8-bit C1 0x9B. SGR has final byte 'm' (0x6D). Parameters are separated by ';' (0x3B).
ext.params — https://invisible-island.net/xterm/ctlseqs/ctlseqs.html xterm ctlseqs 'Character Attributes (SGR)' table: 0 normal, 1 bold, 3 italic, 4 underline, 7 inverse, 22/23/24/27 resets, 30-37 fg, 38 extended fg, 39 default fg, 40-47 bg, 48 extended bg, 49 default bg, 90-97 bright fg, 100-107 bright bg.
ext.params — https://ecma-international.org/publications-and-standards/standards/ecma-48/ ECMA-48 defines SGR and parameter values 0–9, 21–29, 30–39, 40–49 (the standard frame). The 38/48 extended-color forms and 90–107 bright ranges are xterm/ISO 8613-6 conventions layered on top.
#38-5 — https://invisible-island.net/xterm/ctlseqs/ctlseqs.html 38 ; 5 ; Ps selects a foreground color from the 256-color palette (ISO 8613-6 / ITU T.416 colon form, also accepted as the xterm semicolon form).
#38-2 — https://invisible-island.net/xterm/ctlseqs/ctlseqs.html 38 ; 2 ; Pr ; Pg ; Pb selects a direct (truecolor) 24-bit foreground color.

agent: curl -H 'accept: application/json' wire.phall.io/terminal-csi/sgr or /terminal-csi/sgr.json

CSI SGR — Select Graphic Rendition (colors & text attributes)

frame

parameters / subcommands

gotchas

provenance

see also