Tools

Four instruments. Each one measures something that is usually decided by accident. None of them wants an account, an email or a cookie.

Webfont cost measures Fetch the actual WOFF2 files for an Arabic family and add up the bytes a visitor downloads.
Bilingual type scale calculates Build a scale from one base size, with the Arabic companion size and leading worked out.
RTL audit scans Paste markup or CSS and get the physical properties, unmirrored icons and missing direction.
Numeral systems compares Arabic-Indic, Eastern Arabic-Indic and Western digits, and what this browser formats right now.

All four run in your browser. Where a number appears, it was measured in this tab.