Iosevka configuration to mimic the look and feel of Berkeley Mono as closely as possible.
Ioskeley Mono
A free, open-source alternative to Berkeley Mono — built by configuring Iosevka to match its look and feel as closely as possible.
The name is a mashup: Iosevka + Berkeley = Ioskeley.
Live Preview
See Ioskeley Mono in action with real-time editable samples, multiple programming languages, and side-by-side comparison with Berkeley Mono:
Static Preview
| Ioskeley Mono | Berkeley Mono |
|---|---|
 |
 |
Theme: Kintsugi Dark Flared
Theme: Kanagawa Dragon Theme
Installation
Download the latest release from the Releases page.
Which file do I need?
| Situation | Download |
|---|---|
| Editor or IDE (VS Code, JetBrains, Zed…) | IoskeleyMono.zip |
| Terminal with icons (Neovim, Starship…) | IoskeleyMono-NerdFont.zip |
| Arrows or box-drawing look wrong in my terminal | IoskeleyMono-Term.zip |
| Terminal with icons and rendering issues | IoskeleyMono-Term-NerdFont.zip |
| App that can't disable ligatures (Xcode…) | IoskeleyMono-NL.zip |
| Same, but also need Nerd Font icons | IoskeleyMono-NL-NerdFont.zip |
Web / CSS (@font-face) |
IoskeleyMono-Web.zip |
Not sure? Start with
IoskeleyMono.zip.
What's inside each TTF zip?
Every TTF zip contains all three widths, each with hinted and unhinted variants:
Normal/
Hinted/ ← standard-DPI screens (most Windows setups)
Unhinted/ ← high-DPI / Retina (macOS, Linux HiDPI)
SemiCondensed/
Hinted/
Unhinted/
Condensed/
Hinted/
Unhinted/
Install all fonts in your chosen folder — your OS will expose the full weight axis (Thin → Black) automatically. Start with Normal/ if you're unsure which width you prefer.
Installing the fonts
- Download and unzip your chosen file
- Open the width and hint folder that matches your setup
- Select all
.ttffiles and install:- macOS — double-click any font → Install Font, or drag all into Font Book
- Windows — select all → right-click → Install for all users
- Linux — copy to
~/.local/share/fonts/then runfc-cache -fv
About the Term variant
Ioskeley Mono Term uses spacing = "term", which constrains every glyph to its cell boundary. Use it if arrows (→ ← ↑ ↓), box-drawing characters, or ligatures render incorrectly in your terminal (known affected: kitty, Ghostty). The glyph design is identical to the standard variant — it's purely a spacing change.
About the NL variant
Ioskeley Mono NL has all ligature substitutions disabled. Use it in apps that can't toggle ligatures off themselves (e.g. Xcode). Everything else — weights, widths, glyph shapes, metrics — is identical to the standard variant.
Weights
Ioskeley Mono matches Berkeley Mono's full weight axis across all widths:
| Weight | CSS value |
|---|---|
| Thin | 100 |
| ExtraLight | 200 |
| Light | 300 |
| SemiLight | 350 |
| Regular | 400 |
| Medium | 500 |
| SemiBold | 600 |
| Bold | 700 |
| ExtraBold | 800 |
| Black | 900 |
Every weight is available in all three widths, both Upright and Italic.
Design Choices
Ioskeley Mono uses specific character variants and custom metrics to closely match Berkeley Mono's aesthetic.
Custom metrics — vertical proportions, letter spacing, and parenthesis size are tuned to capture Berkeley's compact, geometric feel.
Distinctive glyphs — single-storey g, flat-arc parentheses (), two-circle 8, dotted 0, open-contour 6 and 9, square punctuation dots, and a raised underscore.
For the full list of configuration choices, see private-build-plans.toml.
Building from Source
The font is built automatically via GitHub Actions on every version tag push. To build locally:
git clone https://github.com/ahatem/IoskeleyMono.git
git clone --depth 1 https://github.com/be5invis/Iosevka.git
cp IoskeleyMono/private-build-plans.toml Iosevka/
cd Iosevka
npm install
npm run build -- contents::IoskeleyMono contents::IoskeleyMonoTerm
Output will be in Iosevka/dist/IoskeleyMono/ and Iosevka/dist/IoskeleyMonoTerm/.
Contributing
This project is just a build configuration on top of Iosevka — changes are often just a few lines in private-build-plans.toml. If you spot something off or have an idea, open an issue or send a PR. All contributions are welcome!
Support
If Ioskeley Mono saves you money on a font license, consider buying me a coffee — it keeps the project going!
License & Credits
Ioskeley Mono is a custom configuration of Iosevka. All credit for the original design and build system goes to Belleve Invis and the Iosevka contributors.
Licensed under the SIL Open Font License 1.1.