What is typical hole spacing on a watch strap?

Most leather and rubber two-piece straps use 6–8 mm centre-to-centre spacing between holes.

How do I calculate even spacing?

Usable length between first and last hole divided by (number of holes − 1) gives the centre-to-centre spacing.

Yes. Leave 8–15 mm from the tip of the long end to the first hole and enough material after the last hole for strength.

Calculation mode Number of holes Usable length (first to last hole) mm Desired centre-to-centre spacing mm End margin (tip to first hole) mm

6 mm spacing

Common on dress leather straps – tighter adjustment

7 mm spacing

Very common all-rounder

8 mm spacing

Often seen on sport / rubber straps

Formula: Spacing = (distance from first hole centre to last hole centre) ÷ (holes − 1)

Educational tool only. Punching holes permanently alters the strap. Work carefully and measure twice.

What is centre-to-centre spacing? The distance from the centre of one hole to the centre of the next hole.

How many holes should a strap have? Most two-piece straps have 5–8 holes. Seven is the most common for good adjustment range.

Can I add holes to a finished strap? Yes, but match the existing spacing and hole diameter for a clean result.

Does hole size matter? Yes. The hole must fit the buckle tongue / pin cleanly without being oversized.