Appearance
SGR (Text Styling)
Select Graphic Rendition (SGR) controls text styling: bold, italic, underline variants, colors, strikethrough, and other visual attributes. SGR sequences are the most commonly used escape codes — every TUI framework depends on them for rendering styled text. Support ranges from universal (bold, basic colors) to inconsistent (curly underline, hyperlinks). SGR was one of the first capabilities defined in ECMA-48 (1976). The parameter space has grown from 10 attributes to over 50, with vendors like Kitty adding sub-parameter syntax (4:3 for curly underline) decades after the standard was written. The original VT100 only had bold, underline, blink, and reverse — and blink was controversial even in 1978. The ANSI committee later added colors, but couldn't agree on which shade of "blue" SGR 34 should be, so they left it up to implementors. Forty-eight years later, "is your terminal blue really blue?" is still a frequently asked question.
Analysis2026-04-06
The SGR (Text Styling) category covers 32 features. Top performers (100%): Ghostty, Kitty, iTerm2, Terminal.app, vterm.js and 6 more. Common gaps: Faint/dim (SGR 2) (1 terminal fails), Italic (SGR 3) (1 terminal fails), Double underline (SGR 21) (1 terminal fails).
Terminal Applications
Headless Backends
Parser correctness tested via Termless. A ✓ means the parser accepts the sequence, not that it renders correctly.