A leather harness only looks and feels right when it fits. Too loose and the straps slide and gape; too tight and the rings dig in and restrict breathing. The good news: you only need a soft tape measure and five minutes. This guide shows exactly what to measure, how to read our size chart, and when a custom size is the better choice.
What you need
- A soft fabric tape measure (or a piece of string and a ruler)
- A mirror, or a partner to help
- Light clothing or bare skin – measure the body the harness will sit on

The 3 measurements that matter
1. Chest
Wrap the tape around the fullest part of your chest, just under the armpits and across the nipples. Keep it level all the way round, breathe out normally and don't pull it tight. This is the most important number for chest harnesses.
2. Waist
Measure around your natural waist, usually just above the belly button. Needed for body harnesses and any style with a lower belt.
3. Torso (shoulder to waist)
Measure from the top of the shoulder, down over the chest, to the waist line. This sets the length of the vertical straps so the centre ring sits in the middle of your chest, not up at your throat or down at your stomach.
For full-body styles we may also ask for shoulder width (bone to bone across the back) and upper arm circumference.
Harness size chart
| Size | Chest (in) | Waist (in) |
|---|---|---|
| Small | 34–37 | 28–31 |
| Medium | 38–41 | 32–35 |
| Large | 42–45 | 36–39 |
| X Large | 46–49 | 40–43 |
| XX Large | 50–53 | 44–47 |
Always check the size guide on the product page too, as some styles run differently.
Between sizes?
- Buckle harnesses: choose the larger size. Buckles give several inches of adjustment, so you can tighten a big harness but never loosen a small one.
- Fixed or snap harnesses: choose the size your chest falls in the middle of, or order custom.
- Building muscle or losing weight? Size for your body today and rely on the buckles for small changes.

How a harness should fit
- You can slide two fingers under any strap.
- The centre ring sits flat in the middle of your chest.
- Straps lie flat without twisting and don't cut into the armpits.
- You can take a full, deep breath comfortably.
Full-grain leather softens and moulds to your body over the first few wears, so a harness that feels slightly firm on day one will feel like a second skin within a week.
When to order a custom size
Choose custom if your measurements fall outside the chart, your chest and waist sit in different sizes, or you have a broad, very slim or very long torso. Every piece is handmade in our own workshop, so making it to your exact numbers is simple – just add your measurements at checkout or send us a custom request.
Frequently asked questions
Should I measure over clothes?
Measure over the clothing you plan to wear under the harness. If you'll wear it on bare skin, measure on bare skin.
Will the leather stretch?
Full-grain leather softens and gives slightly with wear, but it won't stretch a full size. Pick the size that fits now.
Can I exchange a harness that doesn't fit?
Standard sizes can be returned within 30 days if unworn. Custom-made items are final sale, so double-check your measurements.
Ready to choose? Browse our leather harnesses for men, or pair one with a matching leather jockstrap.