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Terminal Census ​

Terminfo.dev →

Can your terminal do that?
Interactive feature support matrix for terminal emulators.

What Is the Census? ​

The terminal census is an automated test suite that probes headless terminal backends for feature support — SGR styling, cursor movement, modes, scrollback, text handling, erase operations, and protocol extensions. Each probe writes escape sequences and inspects the resulting terminal state to determine whether a feature works correctly.

Census probes and their results are maintained in the terminfo.dev repository. Visit terminfo.dev for the full interactive matrix with hover tooltips, category filters, and backend comparison.

How It Works ​

  1. Probes — small functions that write ANSI/VT sequences to a backend and assert on terminal state (cell attributes, cursor position, mode flags, scrollback).
  2. Backends — headless terminal emulator libraries (JS, Rust, C, WASM) implementing the TerminalBackend interface from @termless/core.
  3. Matrix — results are aggregated into a feature x backend grid. Each cell is yes, no, or partial (with notes explaining the gap).

The census uses Termless backends to run probes, but the probe definitions and result data live in terminfo.dev.

Relationship to Termless ​

Termless provides the backend abstraction layer that makes the census possible — a uniform TerminalBackend interface across xterm.js, Ghostty, vt100, Alacritty, WezTerm, and others. The census was originally part of the Termless repo but has moved to terminfo.dev as a standalone project.

For backend capabilities relevant to testing (as opposed to the broader terminal feature matrix), see Backend Capabilities and Cross-Backend Conformance.