Planetaire Mono

A monospace font for terminals that combines B612's highly legible letterforms with Hack's complete programming infrastructure and Nerd Font icons.

Why

B612 was designed by Intactile Design for Airbus cockpit displays — optimized for reading under stress, at odd angles, and in poor lighting. Its letterforms are among the most legible ever designed for monospace text.

But B612 alone isn't a complete programming font. It lacks the punctuation refinements, symbol coverage, and icon ecosystem that developers need. Planetaire Mono solves this by merging B612's letters and digits into Hack Nerd Font's base, combining the best of both:

• B612 letterforms for letters, digits, and extended Latin/Greek/Cyrillic
• Modified zero — B612's zero with a center dot added for clear 0 vs O disambiguation, with circle (default) and rectangle (ss01) variants
• Hack punctuation and symbols for {}[]()<> and everything else
• 12,000+ Nerd Font icons including Powerline, Font Awesome, and Devicons

Weights

Planetaire Mono ships with 10 variants across 5 weights:

Variant	Weight	Recommended Use
Regular	400	Normal terminal text
Italic	400	Emphasized text
Medium	500	UI labels, intermediate weight
Medium Italic	500	UI labels italic
Bold	700	Standard bold
Bold Italic	700	Standard bold italic
ExtraBold	800	Terminal bold text
ExtraBold Italic	800	Terminal bold italic

ExtraBold for Terminals

The jump from Regular (400) to standard Bold (700) is often too subtle at terminal font sizes. ExtraBold (800) provides the visual punch that makes bold text — prompts, headings, highlighted output — actually stand out. This is the recommended bold weight for terminal use.

Configure your terminal to use ExtraBold for bold text:

# Ghostty
font-family = "Planetaire Mono"
font-thicken = true

# Alacritty
[font.bold]
family = "Planetaire Mono"
style = "ExtraBold"

# WezTerm
config.font_rules = {{
  intensity = 'Bold',
  font = wezterm.font('Planetaire Mono', { weight = 'ExtraBold' }),
}}

# VS Code terminal
"terminal.integrated.fontWeightBold": "800"

See docs/terminal-config.md for complete configuration examples for Ghostty, Alacritty, WezTerm, iTerm2, Kitty, and VS Code.

Character Coverage

B612's letterforms make commonly confused characters easy to tell apart: Il1| (I, l, 1, pipe), O0o (O, zero, o), rn vs m, 5S, 8B, 2Z.

Coverage includes Latin Extended A/B, Greek and Coptic, Cyrillic, and Latin Extended Additional — over 12,000 glyphs total.

Install

Download

Download the latest release from GitHub Releases:

• PlanetaireMono.tar.xz (recommended, smallest)
• PlanetaireMono.zip

macOS

# Download and extract
curl -L https://github.com/jlevy/planetaire/releases/latest/download/PlanetaireMono.tar.xz | tar xJ
# Install
cp PlanetaireMono-*.ttf ~/Library/Fonts/

Linux

# Download and extract
curl -L https://github.com/jlevy/planetaire/releases/latest/download/PlanetaireMono.tar.xz | tar xJ
# Install
mkdir -p ~/.local/share/fonts/PlanetaireMono
cp PlanetaireMono-*.ttf ~/.local/share/fonts/PlanetaireMono/
fc-cache -fv

Build from Source

Planetaire Mono is built with a Python pipeline that uses fontTools for binary font manipulation.

Prerequisites

• Python 3.12+
• uv (recommended) or pip

Build

# Install dependencies
uv sync --all-extras

# Download source fonts and build all variants
make fonts

# Or step by step:
uv run planetaire build download        # download source fonts
uv run planetaire build planetaire-mono  # build all 10 variants
uv run planetaire validate fonts/output/*.ttf  # validate output

Built fonts are written to fonts/output/.

CLI

The planetaire CLI exposes the individual operations for inspection and debugging:

planetaire info fonts/output/PlanetaireMono-Regular.ttf
planetaire compare font-a.ttf font-b.ttf --ranges 0041-005A
planetaire validate fonts/output/*.ttf

How It Works

The build pipeline:

1. Merge — Copies B612 glyphs (letters, digits 0-9, extended Latin, Greek, Cyrillic) into the Hack Nerd Font base, normalizing UPM from Hack's 2048 to B612's 2000
2. Dotted zero — Adds a center dot to B612's zero for 0/O disambiguation, with circle (default) and rectangle (ss01/zero) OpenType alternate variants
3. Rename — Sets font family metadata to "Planetaire Mono" with correct PostScript names and weight classes
4. Fix — Adds required tables (DSIG), sets embedding flags (fsType=0), and configures grid-fitting (GASP)
5. Validate — Checks glyph coverage, weight metadata, and OpenType features

This is repeated for all 8 variants (Regular, Italic, Medium, MediumItalic, Bold, BoldItalic, ExtraBold, ExtraBoldItalic).

Credits

• B612 — Intactile Design for Airbus (polarsys/b612). The letterforms that make this font special.
• Hack — Chris Simpkins. The base font providing punctuation, symbols, and overall metrics.
• Nerd Fonts — Ryan McIntyre. 12,000+ developer icons including Powerline, Font Awesome, Devicons, and more.
• carlosedp — Carlos Eduardo de Paula's B612 fork with ligatures and Nerd Font patching, which inspired the dotted zero design. Not a build dependency.

License

Planetaire Mono is released under the SIL Open Font License 1.1 (OFL-1.1).

The constituent source fonts carry the following licenses:

• B612: OFL-1.1 + EPL-2.0
• Hack: MIT License
• Nerd Fonts patches: MIT License

See fonts/source/licenses/ for full license texts.

The build tooling (this repository's Python code) is under the MIT License.