What Is Kerning?
Kerning refers to the process of adjusting the spacing between specific pairs of characters in a typeface. Unlike tracking (which adjusts spacing uniformly across a block of text) or leading (which governs line height), kerning is a micro-level intervention — a surgical tweak between two particular glyphs.
Most type designers embed kern tables into their fonts: lookup tables that automatically tighten or loosen space for notoriously awkward pairs like AV, To, WA, or ry. But no kern table is perfect, and at large display sizes, imperfections become glaring.
Why Spacing Feels Wrong Without It
The human eye doesn't perceive space as area — it perceives it as optical weight. Two letters with identical mathematical spacing can look wildly uneven depending on their shapes. Consider:
- Round + Round (OO): Naturally feel closer together
- Straight + Straight (HH): Feel open and even
- Diagonal + Straight (VA): A massive gap forms under the diagonal — the classic kern culprit
When these optical gaps go uncorrected, readers don't consciously notice the problem — they just feel vaguely unsettled, like a picture hanging slightly crooked on the wall.
Kerning vs. Tracking: A Key Distinction
| Feature | Kerning | Tracking |
|---|---|---|
| Scope | Between specific letter pairs | Across entire word/block |
| Purpose | Optical correction | Density/mood adjustment |
| When to use | Headlines, logos, display type | All-caps text, body copy air |
| Controlled by | Font kern tables or manual override | A single numeric value |
How to Kern Like a Pro
- Work at display size. Kern at the size the type will be seen (or larger). Problems invisible at 12pt scream at 72pt.
- Squint or flip it upside down. Removing the meaning from letters lets you see their shapes and the spaces between them more objectively.
- Aim for equal optical volume, not equal measured distance. The white space between each pair should feel the same weight.
- Use the "context switch" trick. Paste your headline into a different typeface temporarily. Returning to the original resets your eye.
- Don't over-kern. Tightening too aggressively destroys legibility. Letters should breathe — just not gasp.
When Kerning Matters Most
Kerning is critical in:
- Logo design — where letter spacing is part of brand identity
- Display headlines — at large sizes, every gap is amplified
- Signage and wayfinding — poor kerning at scale is genuinely confusing
- Print titles and book covers — where craft signals quality
In flowing body text at small sizes, built-in kern tables do most of the work. Trust your font — and your designer.
The Famous "Kern" Game
If you want to sharpen your eye, try Kern Type — a free browser-based game that challenges you to kern letter pairs by feel. It's humbling, educational, and oddly addictive. A well-trained eye for spacing is one of the hallmarks that separates typographers from the rest.
Great kerning is invisible. Bad kerning is unforgettable — for all the wrong reasons.