Inspecting Variable Font Metadata Online
- Variable fonts are OpenType font files that contain multiple style variations in a single file — but they still embed the same metadata as static fonts.
- A metadata viewer reads the family name, version, license, embedding rights, and glyph count from a variable font file just as it does from a static TTF or OTF.
- This guide covers what metadata is accessible and what requires a dedicated variable font axis explorer.
Table of Contents
Variable fonts — OpenType Font Variations, introduced in 2016 — pack an entire type family into a single font file. Where you previously needed separate files for Regular, Bold, Light, and Italic, a variable font file contains the full design space and lets you dial in any point between them.
From a metadata standpoint, variable fonts are still OpenType files. They contain the same name table, OS/2 table, and other metadata tables as static fonts — plus additional tables for the variation axes. A metadata viewer can read the standard embedded fields from a variable font file just as readily as from a regular TTF or OTF.
What Standard Metadata a Variable Font Contains
Variable font files embed the same standard metadata fields as static fonts:
- Family name — the official typeface name (e.g., "Inter Variable," "Source Serif 4")
- Designer — the type designer or foundry
- Version — the version string, which often indicates both the font version and the variation specification version
- Copyright — the copyright notice
- License text and URL — same as static fonts; most modern variable fonts use OFL
- Glyph count — the total glyphs in the default instance
- Weight class — the OS/2 weight class value (typically the default or "regular" instance weight)
- Unicode ranges — which unicode blocks the font covers
- fsType — the embedding permission flags
You can inspect all of these fields by dropping a variable font file (which may have a .ttf extension despite being a variable font) into the WildandFree Font Metadata Viewer.
What This Tool Doesn't Show: Variable Axes
Variable fonts contain an additional table — the fvar (Font Variations) table — that defines the design axes. Common axes include:
- wght — weight axis (e.g., 100–900)
- wdth — width axis (condensed to expanded)
- ital — italic axis (0 to 1)
- slnt — slant axis
- opsz — optical size axis
The metadata viewer surfaces the standard name table and OS/2 fields. The fvar axis data — the specific axis tags, names, min/max/default values — isn't displayed by this tool. For exploring variable axes interactively, dedicated tools like the Google Fonts variable font demo interface or Wakamai Fondue show you the full axis space and let you scrub through variations.
Sell Custom Apparel — We Handle Printing & Free ShippingUsing the Viewer for Variable Font License Checks
The most practically useful thing the metadata viewer tells you about a variable font is its licensing situation. Variable fonts are still subject to exactly the same licensing rules as static fonts.
Google Fonts variable fonts (like Inter, Roboto Flex, Source Serif 4) are all OFL-licensed and have fsType 0 — fully embeddable everywhere. Variable fonts from commercial foundries may carry more restrictive licensing, and some foundries charge extra for variable font access even within the same family.
Drop the file to check: does the license text mention variable font use? What is the fsType value? Is there a separate license URL covering variable-specific terms?
How to Tell If a Font File Is Variable
Variable font files typically use the .ttf extension (less commonly .otf for CFF2-based variable fonts). The filename often includes "Variable," "VF," or axis range information (e.g., "Inter-VariableFont_wght.ttf," "Roboto[wght].ttf").
When you open a variable font in the metadata viewer, the family name field often includes "Variable" as part of the official name. The glyph count may be higher than a comparable static font because variable fonts include additional glyph data for the interpolation masters.
If you're unsure whether a file is variable, the fonttools CLI can confirm it: python3 -c "from fontTools.ttLib import TTFont; f = TTFont('font.ttf'); print('fvar' in f)" returns True for variable fonts.
Inspect Any Variable Font File
Drop a variable font TTF to view its family name, designer, license, embedding rights, glyph count, and unicode ranges — processed locally in your browser.
Open Font Metadata ViewerFrequently Asked Questions
Can I inspect a variable font with the metadata viewer?
Yes. Variable fonts are OpenType files and contain all the standard name table and OS/2 metadata. The viewer reads family name, designer, version, license, fsType, glyph count, and unicode ranges from variable fonts just as it does from static fonts.
Does the viewer show variable font axes?
No. The fvar axis data (axis tags, min/max/default values) isn't displayed. The viewer covers the standard metadata fields. For axis exploration, use a dedicated variable font previewer or fonttools on the command line.
Are variable fonts subject to the same licensing as static fonts?
Yes. Variable fonts are licensed under the same frameworks — OFL, Apache, proprietary desktop, web font. Check the license text and fsType flag the same way you would for any font. Some commercial foundries charge extra for variable font access; check the foundry's terms.
