xterm.js

A terminal emulator written in TypeScript for the browser. It is the engine behind VS Code's integrated terminal, Hyper, Tabby, ttyd, JupyterLab, Theia, and many web consoles.

Identity

• TERM, COLORTERM, and TERM_PROGRAM are set by the host that owns the PTY, not by xterm.js. VS Code sets TERM_PROGRAM=vscode and TERM_PROGRAM_VERSION; other hosts vary.
• DA1: CSI ? 1 ; 2 c ? (configurable by the host through the API).
• DA2: CSI > 0 ; 276 ; 0 c ?.
• XTVERSION: ?

Documentation

• xtermjs.org
• Supported sequences
• API reference
• Releases

Addon model

The core handles parsing, the screen model, mouse and keyboard encoding, and basic rendering. Optional behavior lives in addons that a host must load:

• @xterm/addon-image: Sixel and iTerm2 inline images.
• @xterm/addon-clipboard: OSC 52.
• @xterm/addon-unicode11 (and later Unicode versions): character width tables newer than the built-in Unicode 6 table.
• @xterm/addon-ligatures, @xterm/addon-webgl, @xterm/addon-canvas: rendering only.
• @xterm/addon-web-links: URL detection in text, distinct from OSC 8.

Two hosts on the same core version therefore differ in graphics, clipboard, and width behavior according to which addons they load.

Notable behavior

• Supports truecolor, DECSCUSR, all xterm mouse modes, bracketed paste, alternate screen, OSC 8, underline styles, and synchronized output (2026).
• Does not implement the Kitty keyboard protocol or the Kitty graphics protocol in core.
• The host decides which keys reach the terminal at all; browser and editor keybindings frequently intercept chords before xterm.js sees them.

Version notes

5.x releases; the package moved from xterm to @xterm/xterm in 5.4. See the release notes for VT additions.

Probe

echo "$TERM_PROGRAM $TERM_PROGRAM_VERSION"
tools/query '\033[>c'

Feature support

Records are maintained independently in tdn/terminals/xtermjs.yaml. Unlisted features are unknown. See the comparison for all features.

Feature	Support	As of	Notes and evidence
BEL urgency/visual c0-bel-attention	PartialImported · unverified	Unversioned	Partial import
14/16 pixel sizes csi-14-16-t-pixel-sizes	SupportedImported · unverified	Unversioned	Yes import
18 size in cells csi-18-t-text-size	SupportedImported · unverified	Unversioned	Yes import
22/23 title stack csi-22-23-t-title-stack	SupportedImported · unverified	Unversioned	Yes import
ED 3 (scrollback) csi-3-j-erase-scrollback	SupportedImported · unverified	Unversioned	Yes import
DECRQM csi-decrqm	SupportedImported · unverified	Unversioned	Yes import
DECSLRM / ?69 csi-decslrm	UnsupportedImported · unverified	Unversioned	No ([xterm.js supported terminal sequences](https://xtermjs.org/docs/api/vtfeatures/) lists DECSLRM as unsupported.) import
DECSTBM csi-decstbm	SupportedImported · unverified	Unversioned	Yes import
DECSTR csi-decstr	SupportedImported · unverified	Unversioned	Yes import
ED/EL/ECH/ICH/DCH/IL/DL csi-editing-operations	SupportedImported · unverified	Unversioned	Yes import
REP csi-rep	SupportedImported · unverified	Unversioned	Yes import
SU/SD csi-su-sd-scroll	SupportedImported · unverified	Unversioned	Yes import
Kitty keyboard protocol csi-u-kitty-keyboard	UnknownImported · unverified	Unversioned	?; Open feature request ([xtermjs/xterm.js issue tracker](https://github.com/xtermjs/xterm.js/issues).) import
DECRQSS dcs-decrqss	SupportedImported · unverified	Unversioned	Yes; [vtfeatures](https://xtermjs.org/docs/api/vtfeatures/): `m`, `r`, `SP q` import
Sixel dcs-sixel	SupportedImported · unverified	Unversioned	Yes, addon ([@xterm/addon-image](https://github.com/jerch/xterm-addon-image).) | Also recorded: Yes, addon ([@xterm/addon-image](https://github.com/jerch/xterm-addon-image).); `@xterm/addon-image` import import
XTGETTCAP dcs-xtgettcap	UnknownImported · unverified	Unversioned	?; not in vtfeatures import
1000 mouse dec-mode-1000-mouse	SupportedImported · unverified	Unversioned	Yes import
1002 button motion dec-mode-1002-button-motion	SupportedImported · unverified	Unversioned	Yes import
1003 all motion dec-mode-1003-all-motion	SupportedImported · unverified	Unversioned	Yes import
1004 focus dec-mode-1004-focus	SupportedImported · unverified	Unversioned	Yes ([xterm.js supported sequences](https://xtermjs.org/docs/api/vtfeatures/).) import
1006 sgr mouse dec-mode-1006-sgr-mouse	SupportedImported · unverified	Unversioned	Yes import
1007 alternate scroll dec-mode-1007-alternate-scroll	SupportedImported · unverified	Unversioned	Yes import
1015 urxvt mouse dec-mode-1015-urxvt-mouse	SupportedImported · unverified	Unversioned	Yes import
1049 alternate screen dec-mode-1049-alternate-screen	SupportedImported · unverified	Unversioned	Yes import
2004 bracketed paste dec-mode-2004-bracketed-paste	SupportedImported · unverified	Unversioned	Yes | Also recorded: Yes; ([xterm.js supported sequences](https://xtermjs.org/docs/api/vtfeatures/).) import import
2026 synchronized output dec-mode-2026-synchronized-output	SupportedImported · unverified	Unversioned	Yes import
Grapheme cluster mode (2027) dec-mode-2027-grapheme-clusters	UnknownImported · unverified	Unversioned	?; Per-code-point storage import
?45 reverse wrap dec-mode-45-reverse-wrap	SupportedImported · unverified	Unversioned	Yes import
win32-input-mode dec-mode-9001-win32-input	UnknownImported · unverified	Unversioned	?; Not a Unix protocol; not documented by any of them import
DECSCA/DECSED/DECSEL dec-selective-erase	PartialImported · unverified	Unversioned	Partial import
DEC Special Graphics esc-dec-special-graphics	SupportedImported · unverified	Unversioned	Yes ([xterm.js](https://xtermjs.org/), `src/common/data/Charsets.ts`.) import
OSC 0/2 set osc-0-2-title	SupportedImported · unverified	Unversioned	Yes import
OSC 10/11 query osc-10-11-default-colors-query	SupportedImported · unverified	Unversioned	Yes import
OSC 10/11 set osc-10-11-default-colors-set	SupportedImported · unverified	Unversioned	Yes import
104/110/111 reset osc-104-110-111-color-reset	SupportedImported · unverified	Unversioned	Yes import
OSC 12 cursor osc-12-cursor-color	SupportedImported · unverified	Unversioned	Yes import
iTerm2 osc-1337-inline-images	SupportedImported · unverified	Unversioned	Yes, addon ([@xterm/addon-image](https://github.com/jerch/xterm-addon-image).) | Also recorded: Yes, addon ([@xterm/addon-image](https://github.com/jerch/xterm-addon-image).); `@xterm/addon-image`; also used by the VS Code terminal import import
OSC 4 query osc-4-palette-query	SupportedImported · unverified	Unversioned	Yes import
OSC 4 set osc-4-palette-set	SupportedImported · unverified	Unversioned	Yes import
OSC 52 read osc-52-read	PartialImported · unverified	Unversioned	Partial; Requires `@xterm/addon-clipboard`; the addon's provider decides import
OSC 52 write osc-52-write	PartialImported · unverified	Unversioned	Partial; Requires `@xterm/addon-clipboard`; the addon's provider decides import
OSC 8 hyperlinks osc-8-hyperlinks	SupportedImported · unverified	Unversioned	Yes (5.0) import
256 colors sgr-256-colors	SupportedImported · unverified	Unversioned	Yes import
Italic 3 sgr-3-italic	SupportedImported · unverified	Unversioned	Yes import
Colon form 38:2 sgr-38-2-colon-form	SupportedImported · unverified	Unversioned	Yes import
Truecolor 38;2 sgr-38-2-truecolor	SupportedImported · unverified	Unversioned	Yes import
Underline styles 4:n sgr-4-underline-styles	SupportedImported · unverified	Unversioned	Yes import
Blink 5 sgr-5-blink	SupportedImported · unverified	Unversioned	Yes import
Overline 53 sgr-53-overline	SupportedImported · unverified	Unversioned	Yes import
Underline color 58 sgr-58-underline-color	SupportedImported · unverified	Unversioned	Yes import
Strikethrough 9 sgr-9-strikethrough	SupportedImported · unverified	Unversioned	Yes import
bce terminfo-bce	SupportedImported · unverified	Unversioned	Yes import
Bold-is-bright option text-bold-is-bright	PartialImported · unverified	Unversioned	Partial import
Synthesized box drawing text-box-drawing	SupportedImported · unverified	Unversioned	Yes import
Color emoji rendering text-color-emoji	SupportedImported · unverified	Unversioned	Yes import
Italic face text-italic-face	SupportedImported · unverified	Unversioned	Yes import
Ligatures / shaping text-shaping	PartialImported · unverified	Unversioned	Partial (canvas renderer) import
Bundled Unicode tables text-unicode-tables	SupportedImported · unverified	Unversioned	Yes import