✒️ Nib Size to Letter Height Reference Chart
A general reference for typical x-heights by broad-edge nib width, based on the traditional nib-width counting method used in most calligraphy scripts.
Where the chart's numbers come from
Every row on this page is the same multiplication, done at five nib widths:
x-height = nib width × nib-width count
1 mm → 5 mm 1.5 mm → 7.5 mm 2 mm → 10 mm
2.5 mm → 12.5 mm 3 mm → 15 mm 5 mm → 25 mmA nib width is measured with the pen itself, not a ruler: hold the edge at 90° to the writing line and step square blocks up the page in a staircase, then rule the x-height at the top of the fifth block. The unit travels with the nib, so the same script written with a 1 mm and a 5 mm nib keeps its proportions.
The count changes with the script
Five is the chart's working figure, but its own note gives the usual counts, and they move the answer:
| Script | Nib widths | X-height with a 2 mm nib |
|---|---|---|
| Foundational | ~4 | 8 mm |
| Italic | ~5 | 10 mm |
| Uncial | ~4 | 8 mm |
Ascenders and capitals are counted in the same unit, usually two to three nib widths above the x-height. Pointed-pen hands such as Copperplate have no fixed edge width, so the system does not apply to them.
Frequently asked questions
How many nib widths tall should letters be?
Four to five for the x-height in most broad-edge hands: about four for Foundational and Uncial, about five for Italic. Fewer nib widths give a heavier letter, more give a lighter one.
What x-height does a 2 mm nib give?
10 mm at five nib widths, or 8 mm at four. Multiply the nib width by the count your script uses; the chart on this page lists six common nib sizes at five.
How do I measure a nib width?
Turn the pen so the edge is at 90° to the writing line and print a staircase of touching square blocks up the page. Counting those blocks is the measurement.