Font File Inspector

Inspect OTF/TTF/WOFF/WOFF2 font files showing glyph count, supported characters, and metadata tables.

Tested tool guide Tested browser tools Checked August 16, 2026

What Font File Inspector does and how it behaves

Font File Inspector examines a selected OTF, TTF, WOFF, or WOFF2 file and reports its glyph count, mapped characters, and font tables. The report is derived from information stored inside the font, including Unicode-to-glyph mappings and naming records. The selected font remains in the browser, which is useful when checking licensed or unpublished typefaces. The common surprise is that glyph count and character coverage are not equivalent: a font may contain alternate, ligature, control, or unmapped glyphs that do not represent additional supported Unicode characters.

How the result is produced

Glyph and character reporting

The glyph total comes from the font's glyph-count information, while supported characters come from mappings in its cmap table. These are separate measurements. Several Unicode code points can map to one glyph, and some glyphs may have no direct Unicode mapping because they are alternates, ligatures, components, or internal drawing elements.

Table and name inspection

The inspector identifies metadata tables carried by the font and presents decoded information such as family, subfamily, version, or naming records when those values exist. OTF and TTF files use the OpenType table structure, while WOFF and WOFF2 package corresponding font data in compressed web-font formats. Compression does not remove the distinction between glyph inventory and character mapping.

Good uses

Check whether a downloaded font maps the particular letters, symbols, or scripts required by a document or interface before installing or deploying it.
Compare two font files that have similar filenames and determine whether their embedded family, style, version, glyph count, or table inventory differs.
Investigate a web font supplied as WOFF or WOFF2 when expected characters are missing, without converting the file or uploading it to a remote inspection service.

Limits and checks

A listed Unicode character confirms that the font contains a cmap mapping for it. It does not prove that the glyph is legible, stylistically correct, distinct from another glyph, or suitable for the intended language.
A larger glyph count does not necessarily mean broader Unicode coverage. Unencoded alternates, ligatures, composite components, and other internal glyphs can increase the total without adding directly selectable characters.
Name records may occur in several languages or platform-specific forms, and their wording is supplied by the font producer. A filename, an embedded family name, and a typographic family name can legitimately disagree.

Common questions

Can the inspector prove that a font fully supports a language?

No. The character list can show whether individual Unicode code points have mappings, which is a useful first check. Complete language support can also depend on combining marks, punctuation, localized forms, shaping substitutions, positioning behavior, and readable glyph design. Those requirements cannot be established from a character count alone.

Why is the glyph count higher than the number of supported characters?

The two totals describe different things. A font can contain glyphs reached through shaping rules rather than direct character entry, including ligatures and contextual or stylistic alternates. Multiple characters can also share one glyph, while some glyphs remain unmapped. Therefore neither total can be reconstructed reliably from the other.

References and verification

The behavioral notes were checked against the browser implementation. Standards and primary references below define the relevant format, formula, or platform behavior.