What it does
HarfBuzz provides text shaping and related font tools. Its manual documents scripts, features, variable fonts, glyph clusters, platform integrations and command-line utilities for font work.
HarfBuzz converts Unicode text into the glyphs and positions a font needs to display it. For a quick diagnosis, pass a font file and a short string to hb-shape. Its terminal output shows glyph names or IDs, character clusters, offsets and advances; JSON output is also available. Use hb-view with the same inputs when you need a visual result or a PNG, SVG or PDF proof.
Both tools let you change language, script, direction, OpenType features and variable-font axes. This helps isolate whether an unexpected result comes from a substitution, a position adjustment or a variation setting.
A complete text interface still needs surrounding layout code. Split mixed fonts, sizes and directions into appropriate runs before shaping, and handle bidirectional ordering, line breaks, hyphenation and paragraph justification separately. The library and command-line tools are free under permissive open-source terms.
Strengths
- Documents shaping concepts alongside practical font utilities.
- Covers features, clusters and platform integrations.
Watch out for
- Does not provide paragraph layout, bidirectional processing or line breaking.
- Requires programming or command-line familiarity.
Best for
- Developers implementing multilingual text.
- Type designers diagnosing shaping behavior.
Sources
- HarfBuzz Manual: HarfBuzz Manual (Oct 27, 2026)
- What HarfBuzz doesn't do: HarfBuzz Manual (Oct 27, 2026)
- HarfBuzz copying and license notice (Oct 27, 2026)
- HarfBuzz Utilities (Oct 27, 2026)