Method 1: Tape & Ruler
You will need clear sticky tape, a marker, and a ruler marked in millimeters.
1. Place the tape across the widest part of the nail.
2. Use the marker to mark the exact left and right edges of your nail bed.
3. Remove the tape, lay it flat against the ruler, and note the distance in millimeters.
4. Repeat this for all ten nails.
Method 2: Soft Measuring Tape
You will need a soft measuring tape.
1. Wrap the tape snugly around the widest part of the nail.
2. Record the measurement in millimeters from sidewall to sidewall (where your nail meets the skin).
3. Repeat this for all ten nails.