How to measure
Since any leather or other material that you order for a buckle might have to be handmade then the
correct measurement for that belt is critical.
Please do not assume that your waist measurement is your trouser size as this will certainly result in a belt that is too small.
There is a formula in belt making, since the larger the waist size, the further the trouser loops are spaced from the zipper when tailored. The actual size that you request bespoke, determines that the belt you receive will fit on hole number 3 of five or seven holes and the end of the belt will be adequately caught by the first trouser loop.
1. Decide what you will be wearing.
In general a 1" belt is more sought after these days by women or continental men. The American fashion influence (Halston, CK et al) has brought about a universal standard of 1 1/4" for most casual trousers and suits. 1 1/2" is for jeans and the newer ranges of casual trouser. Best to check what the trouser loops can take.
2. What height on your body will you wear your new belt?
For women, some may want a true waist belt for a skirt and top combo, alternatively their jeans may be 'hipsters'
Men with a large girth will more than often than not wear their belts below their adequacy. Slimmer guys will practically always wear their trousers at the true waist size as stipulated by the manufacturer, but do check.
How to Measure:
Take your existing conventional belt and measure from where the tongue of the buckle is captured by the wrap around of the belt leather to the hole where you are comfortably doing up your favourite belt today.
If the only belt you have carries a buckle with a nipple type fastener, then measure from the nipple to the hole where you are fastening the belt comfortably.
Both of the above apply too if you require just re-leathering. This measurement will provide you with a perfect fitting belt that fastens on the third hole of the five.
The traditional British sizes of buckles are typically 1", 1 1/4" and 1 1/2" for general use, whereas American buckles increase by 1/8" up the scale. If you feel any reticence about increasing the width of the belt from say 1" to 1 1/4", then rest easy for the straps are hand cut with the plough gauge slightly shyer so that the leather passes through both buckle and belt keeper cleanly.