What are kerning pairs?

Kerning pairs are combinations of two glyphs whose default spacing needs manual adjustment in a font — classics like AV, To, or Ya. Type designers work through a list of such pairs in their font editor and assign each one a kerning value. This tool generates those lists automatically from any character set.

What do the AB, A⇄B, and ABA patterns mean?

AB produces straight two-glyph pairs (AV). A⇄B checks both orders at once: each ABA string such as AVA contains AV and VA, so every unordered pair appears exactly once. ABA wraps every ordered pair in its first glyph (AVA, VAV), which makes spacing easier to judge because the eye compares the gap on both sides of the middle glyph.

How do I use the proof strings in a font editor?

Pick the Glyphs, RoboFont, or FontLab format: pairs are written as /glyphname sequences (production or nice names, with uniXXXX fallbacks) that paste straight into Sample Strings, Space Center, or a FontLab glyph window. For other editors, use a portable newline, spaced, or continuous text format.

Can I preview the pairs in my own font?

Yes. Click “Open working font” or drag an OTF, TTF, WOFF, or WOFF2 file onto the page. The font is read in your browser, every pair’s kern value is measured, and the file is never uploaded. Recent fonts are remembered on this device only, and a demo font is available if you just want to look around.

Which languages and scripts are supported?

There are 46 presets covering Armenian, English, French, German, Spanish, Portuguese, Greek, Hebrew, Arabic, Persian, Russian, Ukrainian, Polish, Czech, Georgian, Hindi, Bengali, Tamil, Thai, Korean, Japanese, Chinese, Vietnamese, Turkish, and more — and you can paste any custom glyph set. Where pair kerning isn’t customary (for example Chinese, Thai, or most Indic scripts), the tool says so instead of scoring it.

What are context control strings like HH and OO?

A standard spacing-proof technique: each pair is set between control glyphs with known sidebearings (straight controls like HH or nn, round controls like OO or oo), so you judge the pair against a stable reference instead of in isolation.

Yes — completely free, no account, no upload. Everything runs in your browser, and your session (characters, settings, flagged pairs) is saved locally between visits.

Arabic kerning pairs

Start a kerning proof

Open your working font, then choose a character set. Your proof updates instantly and never leaves this device.

What you can do

Release checkCoverage, kerning and metrics in one report

Guide

Kerning Arabic fonts

Letters from the Arabic preset, set in this page’s text font.

Arabic letters join, so many junctions are connections rather than gaps. Kerning matters most after letters that don't connect to the next one (ا د ذ ر ز و) and around final forms. The same page covers Persian, which adds پ چ ژ گ.

Pair kerning in Arabic is limited. Arabic letters join, so most adjacent pairs are connected rather than kerned. A few designs kern after the non-joining letters (ا د ذ ر ز و) — SF Arabic, Baghdad — but they share no common set of pairs and most Arabic fonts kern none, so no benchmark is generated.

The workbench above opens with the Arabic preset. Other Arabic presets in the alphabet menu: Persian. Open your font to check whether it adjusts any of these pairs at all, and switch to spacing strings to compare each glyph's fit. Your font never leaves this device.

Arabic kerning pairs generator

Proof canvas

What you can do

Kerning Arabic fonts