# TrueType / OpenType Inspector

> Read font tables, name records, glyph counts and licensing flags.

- Page: https://decoder.tools/font-inspector
- Category: File Format & Archives
- Status: live, runs in the browser
- Last reviewed: 2026-10-23

A font inspector parses the SFNT table directory of a TrueType or OpenType font file, listing its tables and decoding the metadata they hold — family and style names, glyph count, units per em and embedding permissions.

## What is the TrueType / OpenType Inspector?

TrueType and OpenType share the SFNT container: a header, a table directory, then the tables themselves, each identified by a four-character tag. The essential ones are head (global metrics and units per em), name (all the human-readable strings), cmap (the character-to-glyph mapping), glyf or CFF (the outlines themselves, the difference between TrueType and PostScript-flavoured OpenType), and OS/2, which carries the fsType embedding permission bits.

Those two facts — what the cmap covers and what fsType permits — answer the questions that actually come up. A missing glyph is a cmap coverage problem, not a rendering bug. And fsType tells you whether a font may legally be embedded in a PDF or served on the web, which is a licensing question with real consequences.

Advanced typography lives in GSUB and GPOS: ligatures, kerning, alternates, contextual substitutions. Their presence tells you whether a font supports the features a design depends on.

## How to use the TrueType / OpenType Inspector

1. Load the .ttf, .otf or .woff file — it is parsed locally.
2. Review the table list and the decoded name records.
3. Check the cmap coverage and the fsType embedding permission bits.

## When to use it

- Working out why a specific character renders as a fallback box.
- Checking whether a font's licence permits web or PDF embedding.
- Confirming a font has the OpenType features a design requires.

## TrueType / OpenType Inspector at a glance

| | |
|---|---|
| Container | SFNT — table directory of 4-character tags |
| Outlines | glyf (TrueType quadratic) or CFF (PostScript cubic) |
| Coverage | cmap table maps characters to glyphs |
| Licensing | OS/2 fsType bits set embedding permissions |

## FAQ

### What is the difference between TTF and OTF?

The outline format. TrueType uses quadratic curves in a glyf table; OpenType may use either that or PostScript cubic curves in a CFF table. Both live in the same SFNT container, and OpenType adds GSUB/GPOS typography tables.

### What does fsType mean?

A field in the OS/2 table encoding the foundry's embedding permissions — installable, editable, print-and-preview only, or restricted. It is a licensing signal that PDF generators and browsers are expected to honour.

### Why is a character showing as a box?

The font's cmap has no glyph for that code point, so the renderer substitutes a fallback. Inspecting the cmap coverage confirms it immediately.