ansi.cat | A fast, read-only viewer for macOS

ansi.cat in 84 seconds

This recording shows real files in ansi.cat: ANSI, XBin and ASCII art, a PETSCII stream, Markdown, code, a patch and hex. It also shows the settings and a change of font. It has a voice, music and captions. The art credits are in the Art section, and the music credit is at the end of the page.

Formats

ansi.cat opens these files. It does not change them.

NFO and ASCII: .nfo .diz .asc .asciCode page 437 in the VGA 8×16 font
ANSI and XBin: .ans .ice .xb24-bit and iCE colours, XBin fonts and palettes
Documents: Markdown, text and codetree-sitter colours
Patches: .diff .patchAlso git diff, show and log -p
Terminal: Command output16, 256 and 24-bit colours
Hex: Binary filesFind text or hex bytes

Art

These windows show real files from art packs on 16colo.rs. The header of each window shows the SAUCE title, the artist and the group.

The artists own the art. ansi.cat shows it with their permission.

The reel uses the art in this list.

ACiD Trip: 22 artists of Blocktronics and ACiD2013
The Big Dig: 10 artists of Mistigris2023
ACiD-100 ANSI cluster: 12 artists of ACiD2004
neon: ville / Fire2024
Tribute: Haliphax / ACiD2013
zhulong: Alpha King / Fire2021
Syncopy: H7 / Blocktronics2021
Warez Ghost: The Elk / Mistigris2020
ACIDVIEW.DAT: ACiD View by Skull Leader and Tasmaniac / ACiD1996

ACiD Trip 22 artists of Blocktronics and ACiD, 2013

ansi.cat shows neon: cyan and magenta neon shapes on black and a tall FIRE sign. — neon ville / Fire, 2024

ansi.cat shows October Cat: an orange and white cat with yellow ears sits on a grey rock above a brown pumpkin. — October Cat Binary Walker / Blocktronics, 2013

ansi.cat shows zhulong, an XBin file with its own font: the head of a red dragon with white teeth. — zhulong Alpha King / Fire, 2021

ansi.cat shows The Prismatic Serpent of Deep Space, an XBin file with its own font: the red and white head of a serpent in a teal spiral. — The Prismatic Serpent of Deep Space The Green Herring / Mistigris, 2026

ansi.cat shows Syncopy, ASCII art in code page 437: the word SYNCOPY in pale blue above the word RELEASE. — Syncopy H7 / Blocktronics, 2021

Markdown and images

Read Markdown with local, embedded, remote and SVG images.

Local images stay inside the document folder or its git repository. Remote images use approved HTTPS hosts.

PNG and PDF exports include the images. Quick Look shows local and embedded images.

A README with a PNG image and an SVG image

PETSCII

See Commodore 64, VIC-20 and PET art. Petmate also supports C128 screens.

Open SEQ streams, screen dumps, Petmate and PETSCII editor files. Select Pepto, Colodore or VICE colours.

Play SEQ streams at modem speeds. Files open with the full image.

ansi.cat shows a SEQ stream of a PETSCII cat head and the word ANSiCAT in Commodore 64 colours, with the play, speed and character set controls. — A SEQ stream with the play, speed and character set controls

SVG

Open SVG images. Read the size in the header.

The app removes scripts, animation and external references. Use Shift+Cmd+S for XML source.

ansi.cat shows the ansi.cat pentagram SVG, a cat head with an inverted pentagram in a circle, at its size of 320 by 320. — The image

The XML source of the ansi.cat pentagram SVG in ansi.cat, with tree-sitter colours. — The XML source with syntax colours

Patches and the ansicat tool

Open a patch file, or pipe a patch into ansi.cat. It shows unified or split views with syntax colours.

Open command output with ansicat. Install it with “Install Command Line Tool…” in the ansi.cat menu.

ansicat change.patch
git diff | ansicat
bat --color=always notes.md | ansicat

ansi.cat shows a patch for a Rust file in the unified diff view, with line numbers, syntax colours and a mark on the changed words. — A patch with marks on the changed words

Keys

Esc clears a selection. It also closes a menu, the find bar or the window.

Cmd+O: Open a file
Cmd+F: Find
Cmd+G: Next match
Cmd+L: Go to a line or hex offset
Shift+Cmd+H: Hex or document
Shift+Cmd+S: SVG image or source
Cmd+= / Cmd+-: Change the art or SVG size
Cmd+0 / Cmd+9: Actual size / fit
] / [: Next / previous change

Install

Copy ansi.cat.app to the Applications folder.
Open ansi.cat.
Open a file, or drop a file on the window.

In the Finder, push Space for a Quick Look preview of art or Markdown.