Why Measuring Your Wrist Matters
Whether you're buying a watch, a fitness tracker, a bracelet, or a medical bracelet, getting your wrist size right is essential. Too tight and it's uncomfortable. Too loose and it slides around or looks off. Most online stores provide a size chart — but they all assume you know your wrist circumference. That's exactly what this tool helps you find.
The Thread Method — Most Accurate At-Home Technique
The most reliable way to measure wrist circumference at home is the thread (or paper strip) method:
- Cut a strip of paper about 1cm wide and 25cm long
- Wrap it snugly around your wrist — not tight, just firm (you should be able to slip one finger underneath)
- Mark the exact overlap point with a pen
- Lay the strip flat on the Full-Screen Ruler and read from the 0mm mark to your pen mark
- That number is your wrist circumference
Measuring for Different Accessories
Watches: Add 10–20mm to your wrist circumference to get the comfortable band length. Most watch bands are sized by their width (18mm, 20mm, 22mm) — that refers to the lug width, not the band length.
Fitness Trackers: Apple Watch, Garmin, Fitbit all size by circumference. Small/Medium typically fits 130–180mm; Large/XL fits 150–220mm.
Bracelets: Add 12–15mm to your measurement for a fitted bracelet, 20–30mm for a relaxed style.
Medical / Hospital Bands: Use exact circumference — these need to be precise.
Wrist Size Conversion Reference
Use the unit converter in the tool above to switch between mm, cm, and inches. Quick reference:
- 150mm = 15.0cm = 5.91 inches
- 165mm = 16.5cm = 6.50 inches
- 180mm = 18.0cm = 7.09 inches
- 195mm = 19.5cm = 7.68 inches