How to Measure Your Wrist for a Watch

You need a tailor's tape, or a strip of paper and a ruler. Not a steel tape measure — it will not conform to the shape of your wrist and it will read long.

• 1. Measure where you actually wear the watch. That is just behind the wrist bone, toward the forearm — not over the bone itself, which reads one to two millimetres larger and will have you buying a strap that gapes.
• 2. Snug, not tight. The tape should sit against the skin without compressing it. A good test: you should be able to slide one fingertip under it with mild resistance.
• 3. Measure bare skin. Over a shirt cuff or a sleeve adds several millimetres, which is exactly the amount of error that makes a bracelet not close.
• 4. Write it down in both units. Watch brands publish case dimensions in millimetres and strap sizes in both, so having both numbers saves you converting under pressure in a shop.
• 5. Measure in the evening if you can. Wrists swell slightly through the day and in heat. Sizing a bracelet to your morning measurement is how you end up loosening it every afternoon.

With a paper strip: wrap it, mark where the end overlaps, lay it flat against a ruler and read the distance to the mark. It is as accurate as a tape and you already own the materials.

Three measurements on the watch determine whether it fits, and they matter in this order.

• Lug-to-lug — the one that matters most. The distance from the tip of one lug to the tip of the opposite one: the watch's actual footprint on your wrist. It has to be shorter than the flat top of your wrist, or the lugs overhang the edge and the case rocks. This is why a 37 mm watch with long lugs can fit worse than a 41 mm watch with short ones. Not every maker publishes it; where they do not, try the watch on or buy from somewhere that takes returns.
• Thickness against diameter. The ratio is what the eye registers. A 35 mm case at 10.93 mm thick — the Tissot PRX 35 — reads properly proportioned; the same diameter at 13 mm reads like a bottle cap and will not slide under a cuff. On a larger wrist the same rule holds in reverse: a 42.5 mm case at 12.25 mm looks more deliberate than a 46 mm case at 15 mm.
• Lug width — the strap problem. Measured between the lugs, in millimetres, and it determines what straps you can buy at all. 20 mm and 22 mm give you the entire aftermarket; 14, 17 and 21 mm cut it to a fraction.

Diameter comes fourth, and only as a rough sanity check. It is the number in every advertisement because it is the easiest one to print.

This is where wrist circumference actually gets used, and where both ends of the size range run into trouble.

Two-piece straps are usually supplied in a 120 mm / 75 mm pairing — the long side and the short side, measured from the lug. That suits most wrists between about 6.25 and 7.75 inches. Below that you are tucking a lot of excess into the keeper; above it you are on the last hole or past it. Both problems have the same fix: most serious strap makers offer the same reference in short and long or XL lengths, and they do not charge extra for it. Check the stated strap length, not the lug width — they are different measurements and shops confuse them constantly.

Steel bracelets ship with a fixed number of removable links plus a few millimetres of micro-adjustment in the clasp. Removing links is easy; adding them means buying extra links from the manufacturer, which is slow, expensive and sometimes impossible on a discontinued reference. If your wrist is above about 7.75 inches, ask about link availability before you buy, or choose a watch with a tool-free link system or an adjustable dive clasp. Our metal bracelet guide covers clasp types and micro-adjustment in detail.

NATO straps sidestep all of this: one long band, many holes, and they fit essentially any wrist. They are also the cheapest way to make a watch work for the beach — see our NATO guide.

If you are buying a strap for a watch you already own and do not know the lug width, you can measure it in thirty seconds. Close the lugs side of the watch toward you, and measure the gap between the inside faces of the two lugs — not the outside of the case — in millimetres. A plastic ruler is accurate enough; digital calipers are better and cost very little.

Lug widths are almost always even numbers (18, 20, 22, 24 mm), so if you measure 19.5 mm you have a 20 mm fitting. Odd widths do exist — Tissot's Gentleman uses 21 mm, Orient's Bambino 21 mm, some Junghans references 17 mm — and they are worth knowing about before you fall for a strap you cannot buy in your size.

A quick-release strap is the easiest upgrade on any watch with standard lugs: spring bars with a sliding tab, so you can change straps with a fingernail instead of a tool.

Live Amazon price: $32.99 — as of October 11, 2026. Prices move daily; the figure at checkout is the one that applies.

Once you have your measurement, here is a correctly sized starting point in each band. All three are watches we recommend elsewhere on their own merits, picked here because their proportions suit a specific wrist.

Under 6.5 inches — Tissot PRX 35 mm

Who it is for: the slim-wristed buyer who wants one watch that reads dressy. At 10.93 mm thick it slides under a cuff, and the Powermatic 80 movement clears a weekend off the wrist. The limitation to know: the bracelet is integrated, so you cannot fit a strap to it at all.

Live Amazon price: $795.00 — as of October 11, 2026. Prices move daily; the figure at checkout is the one that applies.

6.5 to 7.25 inches — Hamilton Khaki Field Automatic 38 mm

Who it is for: almost anybody in the middle of the range. A 47 mm lug-to-lug is the safest footprint in this guide, 11 mm of thickness is modest, and the 20 mm lugs mean every strap length and material is available to you. The H-10 movement gives 80 hours of reserve and sapphire keeps it looking new.

Live Amazon price: $795.00 — as of October 11, 2026. Prices move daily; the figure at checkout is the one that applies.

Over 7.25 inches — Citizen Promaster Diver BN0151-09L

Who it is for: the larger-wristed buyer who wants a watch that looks proportionate and a strap that actually reaches. Forty-four millimetres with 20 mm lugs is the useful combination: the case suits the wrist and the lug width means XL straps are easy to find. It is also ISO-certified to 200 m and light-powered, so there is nothing to wind or replace.

Live Amazon price: $350.00 (list $450.00, 22% off) — as of October 11, 2026. Prices move daily; the figure at checkout is the one that applies.

Measuring over the wrist bone. It reads one to two millimetres large, which is enough to make a bracelet gape or a strap sit on the wrong hole.

Shopping on diameter. The single most common error. Lug-to-lug decides whether the watch sits flat; diameter only tells you how much dial you get.

Sizing a bracelet in the morning. Wrists swell through the day. Size it in the evening, or to the loosest comfortable setting.

Trusting a photo on a wrist that is not yours. Wrist shots are taken on wrists whose measurement is almost never published. Use the numbers.

Forgetting the strap in the budget. If your wrist is at either end of the range, assume you will buy a short or long strap. It is a $30 line item that makes the watch wearable.