mdcat-ng

Render Markdown in the terminal. Inline images, syntax-highlighted code, hyperlinks, an interactive viewer.

Forked from swsnr/mdcat.

What it is

Two binaries. mdcat renders a Markdown file to stdout; mdless opens an interactive view over the same output.

Inline images work natively on iTerm2, Kitty, WezTerm, Ghostty, Rio, VS Code, and Terminology, and via DEC Sixel on Foot, Contour, mlterm, Windows Terminal (1.22+), and xterm -ti vt340. When the terminal can't render an image, links fall back to OSC 8 hyperlinks. Fenced code blocks are highlighted with syntect.

mdless renders the document once, pins the bytes in a buffer, and scrolls in place. Images are disabled during the rendering.

Install

cargo install mdcat-ng

Installs both mdcat and mdless. libcurl is required at build time — macOS bundles it, Debian/Ubuntu want libcurl4-dev, Fedora curl-devel.

Prebuilt tarballs are attached to every release

mdcat

mdcat README.md                # render to stdout
curl -sL URL | mdcat -         # from stdin
mdcat file1.md file2.md        # concatenate renders
mdcat --paginate FILE          # pipe through $PAGER / less -r
mdcat --columns 80 FILE        # pin wrap width
mdcat --ansi FILE              # force styling when stdout isn't a TTY
mdcat --detect-terminal        # report the detected terminal + caps

Full flag list: mdcat --help or mdcat(1).

Piped output

When stdout is a pipe, styling and image escapes drop and the output is plain text — same convention as cat, grep, and ls. If you want colour through a pipe, pass --ansi or keep LESS=-R in the environment.

tmux and GNU screen

Set allow-passthrough on in the tmux config and image escapes reach the underlying terminal. Screen triggers the same DCS wrap automatically from $STY.

Remote images

HTTP images are not fetched by default. Opt in explicitly:

mdcat --remote-images README.md

mdless

Interactive Markdown viewer — vi-style scrolling, live search with highlight, heading jumps, TOC modal, bookmarks.

Keys

Flags

Terminal support

1. Detected at runtime via a Primary Device Attributes probe unless --no-probe-terminal is set. If your terminal advertises Sixel but the probe times out, bump the window with --probe-timeout-ms 200.

SVG images render via resvg; its support matrix lists the SVG features that round-trip faithfully.

Markdown extensions

Beyond CommonMark:

• Pipe tables, task lists (- [x]), strikethrough (~~text~~)
• GFM alert blockquotes (> [!NOTE], > [!TIP], > [!IMPORTANT], > [!WARNING], > [!CAUTION])
• Smart punctuation (curly quotes, en/em dash, ellipsis)
• Footnotes, definition lists, wiki links ([[Page]], [[Page|label]])

Not supported: math ($inline$, $$block$$), inline markup inside table cells (plain text only), cell reflow — cells truncate with ….

Library use

use mdcat::{push_tty, Environment, Settings, TerminalProgram, Theme};
use pulldown_cmark::Parser;
use syntect::parsing::SyntaxSet;

let markdown = "# Hello\n\nRendered with **mdcat**.\n";
let settings = Settings {
    terminal_capabilities: TerminalProgram::Ansi.capabilities(),
    terminal_size: Default::default(),
    multiplexer: mdcat::Multiplexer::None,
    syntax_set: &SyntaxSet::load_defaults_newlines(),
    theme: Theme::default(),
    wrap_code: false,
};
let env = Environment::for_local_directory(&std::env::current_dir()?)?;
let handler = mdcat::create_resource_handler(mdcat::args::ResourceAccess::LocalOnly)?;

let mut out = Vec::new();
push_tty(&settings, &env, &handler, &mut out, Parser::new(markdown))?;

Packaging

A cargo install gives you both binaries. Package metadata:

• Manpage: asciidoctor -b manpage -a reproducible mdcat.1.adoc. Symlink mdless.1 to the same manpage.
• Shell completions: mdcat --completions {bash,zsh,fish}, same for mdless.

Troubleshooting

MDCAT_LOG=trace turns on full trace logging; scope it with MDCAT_LOG=mdcat::render=trace for a single module. Logs go to stderr.

mdcat --detect-terminal prints the detected terminal, the multiplexer (if any), and whatever the DA1 probe discovered — the first thing to check if an image protocol isn't firing where you expect it to.

Contributing

See CONTRIBUTING.md. The short version is cargo fmt --check && cargo clippy --all-targets --all-features -- -D warnings && cargo test --all-targets before you open a PR.

Licence

MPL-2.0, with a handful of files dual-licensed Apache-2.0. File headers mark the applicable licence. See LICENSE and the CHANGELOG for release history.