Ounces, irons and millimetres, made clear
Leather thickness, in plain numbers
This site explains what leather ounces and irons mean, how to turn them into millimetres and inches, and how to check a piece yourself. It also looks at which thickness suits wallets, belts and other everyday projects.
All the thickness notes
What Leather Ounces MeanA hide listed as 3-4 oz isn't describing how heavy it feels. Here's what the ounce number measures in leathercraft and where the confusion starts.
Leather Ounces to Millimeters and InchesTurn a leather ounce rating into inches and millimetres with one simple rule, plus a table for the common weights from 1 oz to 8 oz.
What an Iron Is in Leather ThicknessAn iron is a small unit of leather thickness, generally used for sole leather. See how it compares with the ounce and the millimetre.
Measuring Leather Thickness at HomeHow to check the real thickness of a leather piece with a slotted gauge or a caliper, where to measure, and how to avoid squashing the reading.
Why Thickness Varies Across a HideWhy thickness varies across a leather hide, what a range like 3-4 oz on the label means, and what splitting does.
Leather Thickness for Wallets and Card HoldersWhich leather weights suit wallet interiors and exteriors, and why the combined thickness of the layers matters for slim small goods.
Leather Thickness for Belts and StrapsWhat leather weight belts and straps usually use, and how to cut a strap safely.