CLI options

Option	Values	Description
`-font`	Path to a `.ttf` or `.otf` file	Input font; also accepted as the first positional argument. Required unless using `-varfont`.
`-imageout`	Output image path	Atlas image destination. Default: last input font path with its extension replaced by `.png`.
`-json`	Output `.json` path	Exports metrics, Unicode glyph layout, and kerning. Default: last input font path with its extension replaced by `.json`.
`-chars`	Code points, ranges, or quoted strings, e.g. `'[0x20, 0x7e], "áéíóúñ"'`	Characters to include. Default: printable ASCII (`U+0020`–`U+007E`).
`-charset`	Text file path	Reads Unicode character selection from a UTF-8 or ASCII file instead of inline `-chars`.
`-type`	`mtsdfx`, `mtsdf`, `msdf`, `sdf`	Atlas type. Default: `mtsdfx`, with separate RGB and alpha distance ranges.
`-size`	Positive number	Glyph size in pixels per em. Default: `64`, unless `-minsize` is supplied.
`-pxrange`	Positive number	Total symmetric distance range in pixels; RGB range for `mtsdfx`. Default: `16` (−8 to +8).
`-effectpxrange`	Positive number ≥ `-pxrange`	Alpha/effect range in pixels, only for `mtsdfx`. Default: `max(size / 2, pxrange)` (`32` with CLI defaults).
`-yorigin`	`bottom`, `top`	Output Y-axis direction: upward (`bottom`, default) or downward (`top`).
`-format`	`png`, `binfloat`	Image encoding: 8-bit PNG or raw little-endian 32-bit floats. A `.png` path selects PNG; `mtsdfx` only supports PNG.
`-allglyphs`	No value	Packs every glyph, including unmapped glyphs; JSON omits glyphs without Unicode mappings.
`-varfont`	`"font.ttf?wdth=75&wght=700"`	Input variable font with axis values. Quote the entire argument.
`-minsize`	Positive number	Minimum pixels per em; uses the largest size that fits the same atlas dimensions.
`-glyphs`	Glyph indices or ranges, e.g. `'0, 1, [10, 20]'`	Selects font-specific glyph indices instead of Unicode characters.
`-glyphset`	Text file path	Reads glyph indices and ranges from a file instead of inline `-glyphs`.
`-csv`	Output `.csv` path	Exports glyph identifiers, advances, and bounds as an additional layout file.
`-fontname`	Name	Sets the font name in output metadata.
`-and`	No value	Starts another font input group in the same atlas; character selection carries forward.
`-printvaraxes`	No value	Lists the input font's variation axes without creating default outputs.
`-threads`	Integer ≥ `0`	Accepted for compatibility; this WASM build always runs sequentially.

For more details, see the official msdf-atlas-gen repository.

See MTSDFX for details on the default atlas type and its distance ranges.