/Web APIs


Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.

The FontData interface of the Local Font Access API represents a single local font face.

Instance properties

FontData.family Read only Experimental

Returns the family of the font face.

FontData.fullName Read only Experimental

Returns the full name of the font face.

FontData.postscriptName Read only Experimental

Returns the PostScript name of the font face.

FontData.style Read only Experimental

Returns the style of the font face.

Instance methods

FontData.blob() Read only Experimental

Returns a Promise that fulfills with a Blob containing the raw bytes of the underlying font file.


For a working live demo, see Font Select Demo.

Font enumeration

The following snippet will query for all available fonts, and log metadata. This could be used, for example, to populate a font-picker control.


async function logFontData() {
  try {
    const availableFonts = await window.queryLocalFonts();
    for (const fontData of availableFonts) {
  } catch (err) {
    console.error(err.name, err.message);

Accessing low-level data

The blob() method provides access to low-level SFNT data — this is a font file format that can contain other font formats, such as PostScript, TrueType, OpenType, or Web Open Font Format (WOFF).


async function computeOutlineFormat() {
  try {
    const availableFonts = await window.queryLocalFonts({
      postscriptNames: ["ComicSansMS"],
    for (const fontData of availableFonts) {
      // `blob()` returns a Blob containing valid and complete
      // SFNT-wrapped font data.
      const sfnt = await fontData.blob();
      // Slice out only the bytes we need: the first 4 bytes are the SFNT
      // version info.
      // Spec: https://docs.microsoft.com/en-us/typography/opentype/spec/otff#organization-of-an-opentype-font
      const sfntVersion = await sfnt.slice(0, 4).text();

      let outlineFormat = "UNKNOWN";
      switch (sfntVersion) {
        case "\x00\x01\x00\x00":
        case "true":
        case "typ1":
          outlineFormat = "truetype";
        case "OTTO":
          outlineFormat = "cff";
      console.log("Outline format:", outlineFormat);
  } catch (err) {
    console.error(err.name, err.message);


Browser compatibility

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari WebView Android Chrome Android Firefox for Android Opera Android Safari on IOS Samsung Internet
FontData 103 103 No No No No No No No No No No
blob 103 103 No No No No No No No No No No
family 103 103 No No No No No No No No No No
fullName 103 103 No No No No No No No No No No
postscriptName 103 103 No No No No No No No No No No
style 103 103 No No No No No No No No No No

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