Fonts and Text Rendering

Font family, size, weight, and ligatures.

The same file rendered across a few monospace families:

JetBrains Mono (bundled default)

Menlo (macOS system)

IBM Plex Mono

Google Sans Code

Ubuntu Sans Mono

Cousine

Install font

Otty can read fonts you've installed on your system.

Otty auto-discovers any font you drop into:

~/.config/otty/fonts/

You do not need to install fonts system-wide via Font Book — Otty registers files in this folder with CoreText at launch, so they're available to the Font Family picker and to font-family in config.toml.

Accepted formats

.ttf, .otf, .ttc, .otc (other extensions are ignored, case-insensitive).

Steps

1. Open the folder. From the in-app picker: Settings → Appearance → Font Family → Open font folder. Or in a shell: open ~/.config/otty/fonts.
2. Drop a font file (.ttf / .otf / .ttc / .otc) into the folder. You can drop a whole release zip's ttf/ contents — Otty filters by extension and ignores anything else.
3. Open Settings → Appearance. The font now appears in the Font Family combobox.

If Settings was already open when you added the file, close and reopen the Settings panel to trigger a rescan.

CLI

You can also run otty font import <font file path> to import fonts from local files.

Change Font

Apply the font

After it shows up in the picker, set it from Settings → Appearance → Font Family:

• Global — writes to ~/.config/otty/config.toml, applies everywhere.
• Theme — writes to the active theme TOML, travels with the theme.
• Fallback — comma-separated list, used when the primary font lacks a glyph (CJK, icons).

Or edit config.toml directly:

font-family          = "Iosevka Term"
font-family-fallback = "Sarasa Mono SC, Symbols Nerd Font Mono"
font-size            = 13

Use different font weight

By default the system picks bold / italic variants of the active family automatically. To override, turn off the Auto-match weight & style toggle, then pick fonts under all variants / weights:

Font Size

You can configure font size from Settings → Appearance → Text, from the menu bar, or using the shortcut keys ⌘+/⌘-/⌘0.

Line Height (Cell Height)

You can configure line height from Settings → Appearance → Text. Options are:

• Default: Use what your theme TOML defines
• Compact: Use line height of 1.0
• Loose: Use line height of 1.2
• Custom: Set your own multiplier, like 1.0 or 1.5. Or choose Adjust Cell Height to add or remove a fixed number of pixels from the current cell height.

The same git log, Compact vs Loose:

Compact (line height 1.0)

Loose (line height 1.2)

Text Rendering

Ligatures

You can configure text ligatures from Settings → Appearance → Text.

Values:

• off — no ligatures (default).
• calt — standard ligatures plus contextual alternates (=>, !=, >=, …).
• dlig — also enable discretionary ligatures.

Usually, their difference is (samples below are from the Iosevka font):

Setting	What it does
off	Ligation off — glyphs render individually.
calt	Standard ligatures and contextual alternates — the default in most editors.
dlig	Everything in calt plus discretionary ligatures.

By default ligatures are suppressed inside runs of letters and digits (so they only fire on symbol sequences). To apply them everywhere, add:

font-ligatures-alphabet = true

Text Style (Bold / Italic / Underline / Blink)

Programs running in the terminal can ask for text to be bold, italic, underlined, or blinking (through standard SGR escape sequences). From Settings → Appearance → Text you decide how Otty honors each of those requests.

Bold and Italic each offer four modes:

• Auto (default) — use the font's real bold / italic face, borrowing from your fallback fonts if the primary family doesn't ship one.
• Off — ignore the request entirely: bold text renders at normal weight, italic text stays upright. Handy when a font's bold is heavier than you like.
• Primary Only — use the bold / italic face only when your primary font has one; never pull it from fallback fonts.
• Synthetic — when no real face exists, fake it: Otty algorithmically thickens (faux bold) or slants (faux italic) the regular glyphs.

Underline (on by default) — whether underlined cells actually draw the underline. Turning it off only affects SGR underlines; link underlines (⌘-hover / OSC 8) and strikethrough are unaffected.

Blink (off by default) — some programs mark text as blinking (SGR 5 / 6). Left off, blinking text renders steady; turned on, those cells blink on and off at about 1 Hz. It's off by default because blinking is an accessibility concern and is more often emitted by accident than on purpose.

Text Styles Preview

Font Blending

Settings → Appearance → Text → Font Blending controls how glyph edges are anti-aliased onto the background — which mostly changes how thick thin text looks, especially dark text on a light theme.

Unless your text looks too thin or too heavy, leave this on Default. Each mode below is shown in both a dark and a light theme:

Setting	What it does
Default	Defer to the active theme (which falls back to srgb-over). Recommended.
srgb-over	Otty's baseline; blends so stroke weight lands where the font designer intended.
Dark Light
macos-like	Matches the platform's native blending (on macOS, the Display P3 path), closest to how other Mac apps render text.
Dark Light
linear	Physically-correct linear-light blending. Pure white stays pure white, but thin dark strokes come out ~15% lighter.
Dark Light
perceptual	Like linear, but boosts thin dark text back toward its intended weight. A good pick if you like linear but find text too faint.
Dark Light

It's a subtle, taste-driven setting — switch between a couple of modes with text on screen and keep whichever looks crispest to you.

See also

• Themes — pairs with font choices.
• Unicode and Text Styles — how glyphs flow through the renderer.