Watch Case Size & Fit Calculator

Find the perfect watch size for your wrist. Calculate ideal case diameter, lug-to-lug fit, and visual proportions.

Wrist Size to Case Size

Get recommended watch case sizes based on your wrist measurements.

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Lug-to-Lug Fit Check

Check if a specific watch's lug-to-lug distance fits your wrist properly.

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Visual Proportion Calculator

Calculate the wrist coverage ratio and visual impact of a watch on your wrist.

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Formula

Ideal Case Size = Wrist Circumference x 0.22 + Style Offset | Wrist Coverage = Case Diameter / Wrist Width x 100% | Max L2L = Wrist Width

Frequently Asked Questions

What watch size is right for my wrist?
For 6-6.5" wrists: 36-40mm. For 6.5-7": 38-42mm. For 7-7.5": 40-44mm. For 7.5"+: 42-46mm+. Lug-to-lug distance should not exceed your wrist width for optimal fit.
What is lug-to-lug distance and why does it matter?
Lug-to-lug is the tip-to-tip measurement of the lugs. It determines how the watch sits on your wrist more than diameter alone. Ideally, the L2L should not exceed your wrist width. Overhanging lugs look awkward and can be uncomfortable.
Is a 40mm watch too big for a small wrist?
Not necessarily. A 40mm watch with short lugs (under 48mm L2L) can wear well on a 6" wrist. Case thickness also matters - a thin 40mm wears smaller than a thick 38mm. Always consider all dimensions, not just diameter.

Watch Sizing Guide

Finding the right watch size is about more than just case diameter. The relationship between case size, lug-to-lug distance, thickness, and your wrist dimensions determines whether a watch looks proportional and feels comfortable.

Key Measurements

Case Diameter: The most quoted specification, but only part of the picture. Measured across the widest point of the case (excluding crown).

Lug-to-Lug: Often more important than diameter. The lugs should not extend past the flat top of your wrist. Some 40mm watches have 50mm+ L2L while others keep it under 47mm.

Case Thickness: Affects how the watch wears on your wrist. Under 10mm is considered thin, 10-13mm is standard, and over 14mm is thick. Thick watches can be top-heavy and catch on shirt cuffs.

Wrist Coverage Ratio: The ideal coverage is 60-75% of your wrist width. Under 50% looks too small; over 80% looks oversized.

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