Appearance
Cell Size Reporting (OSC 1337)
OSC 1337 ; ReportCellSize queries the terminal for the dimensions of a single character cell in pixels. The response is OSC 1337 ; ReportCellSize=height;width ST. This is essential for pixel-accurate image rendering protocols (sixel, iTerm2 inline images, kitty graphics) where applications need to know the exact pixel dimensions of cells to scale images correctly.
How this is tested: Send OSC 1337 ; ReportCellSize, verify the terminal responds with pixel dimensions.
Analysis2026-03-26
Supported by 1 of 4 terminals (25%). Not supported by: Ghostty, Kitty, Terminal.app. Part of the Rich TUI baseline.
Supported by 1 of 11 backends (9%)
Terminal Applications
| Terminal | Version | Support | Notes |
|---|---|---|---|
| iTerm2 | 3.6.9 | ✓ yes | |
| Ghostty | 1.3.1 | ✗ no | No OSC 1337 ReportCellSize response |
| VS Code | 1.112.0 | ✗ no | No OSC 1337 ReportCellSize response |
| Warp | 0.2026.03.18.08.24.03 | ✗ no | No OSC 1337 ReportCellSize response |
| Cursor | 2.6.21 | ✗ no | No OSC 1337 ReportCellSize response |
| Kitty | 0.46.2 | ✗ no | No OSC 1337 ReportCellSize response |
| Terminal.app | 2.15 | ✗ no | No OSC 1337 ReportCellSize response |