Font Fingerprinting

Font fingerprinting techniques rely on measuring the dimensions of HTML elements filled with text or single Unicode glyphs. However, font rendering in web browsers can be affected by multiple factors, leading to subtle differences in these measurements.

Font metrics measurement is a brute force method that tries different fonts from a large dictionary of known typefaces. By comparing the size of the rendered element to the default values, this method can determine if a font is present on the system.

Unicode glyphs measurement technique uses special Unicode characters with a large font size and default letterforms as a font-family to create fingerprints by hashing the obtained measurement results.

Font Metrics
Fingerprint	✔ 18cf7a2d6799cb50778ef42c909b4232
Report	22 fonts and 8 unique metrics found
	4827,149 default, sans-serif, cursive, fantasy 4920,149 serif 3797,149 monospace 3845,149 DejaVu Sans Mono 4968,149 DejaVu Serif 4705,185 Noto Sans CJK HK, Noto Sans CJK JP, Noto Sans CJK KR, Noto Sans CJK SC, Noto Sans CJK TC 3412,185 Noto Sans Mono CJK HK, Noto Sans Mono CJK JP, Noto Sans Mono CJK KR, Noto Sans Mono CJK SC, Noto Sans Mono CJK TC 5076,184 Noto Serif CJK JP, Noto Serif CJK KR, Noto Serif CJK SC, Noto Serif CJK TC
Unicode Glyphs
Fingerprint	✔ 954fe0bc
	glyph default sans-serif serif monospace cursive fantasy U+20B9 1018,1862 1018,1862 1018,1862 783,1514 1018,1862 1018,1862 U+2581 1230,1862 1230,1862 1230,1862 783,1514 1230,1862 1230,1862 U+20BA 1018,1862 1018,1862 1018,1862 783,1514 1018,1862 1018,1862 U+A73D 1309,1862 1309,1862 1319,1862 1063,1514 1309,1862 1309,1862 U+FFFD 1641,1862 1641,1862 1641,1862 783,1514 1641,1862 1641,1862 U+20B8 1018,1862 1018,1862 1018,1862 783,1514 1018,1862 1018,1862 U+05C6 706,1862 706,1862 706,1862 574,1514 706,1862 706,1862 U+1E9E 1230,1862 1230,1862 1327,1862 999,1514 1230,1862 1230,1862 U+097F 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+F003 1563,1862 1563,1862 960,1862 783,1514 1563,1862 1563,1862 U+1CDA 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+17DD 2356,1862 2356,1862 2356,1862 1565,1514 2356,1862 2356,1862 U+23AE 834,1862 834,1862 834,1862 783,1514 834,1862 834,1862 U+0D02 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+0B82 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+115A 1472,2317 1472,2317 1472,2317 1196,1882 1472,2317 1472,2317 U+2425 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+302E 2000,2317 2000,2317 2000,2317 1625,1882 2000,2317 2000,2317 U+A830 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+2B06 1341,1862 1341,1862 1341,1862 783,1514 1341,1862 1341,1862 U+21E4 1341,1862 1341,1862 1341,1862 783,1514 1341,1862 1341,1862 U+20BD 1018,1862 1018,1862 1018,1862 783,1514 1018,1862 1018,1862 U+2C7B 785,1862 785,1862 885,1862 638,1514 785,1862 785,1862 U+20B0 1018,1862 1018,1862 1018,1862 783,1514 1018,1862 1018,1862 U+FBEE 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+F810 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+FFFF 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+007F 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+10A0 1398,1862 1398,1862 1156,1862 1136,1514 1398,1862 1398,1862 U+1D790 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+0700 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+1950 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+3095 1600,2317 1600,2317 1600,2317 1300,1882 1600,2317 1600,2317 U+532D 1600,2317 1600,2317 1600,2317 1300,1882 1600,2317 1600,2317 U+061C 0,1862 0,1862 0,1862 0,1514 0,1862 0,1862 U+20E3 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+FFF9 0,1862 0,1862 0,1862 783,1514 0,1862 0,1862 U+0218 1016,1862 1016,1862 1096,1862 783,1514 1016,1862 1016,1862 U+058F 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+08E4 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+09B3 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+1C50 960,1862 960,1862 960,1862 783,1514 960,1862 960,1862 U+2619 1434,1862 1434,1862 1434,1862 783,1514 1434,1862 1434,1862

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