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Watch tools
Thirteen calculators for the questions that come up when you are buying, sizing or living with a watch. Everything runs in your browser, nothing is uploaded, and none of it needs an account.
Size and fit
Watch size calculator
Enter your wrist size and see the recommended case diameter and maximum lug-to-lug, drawn to scale on a wrist.
Watch size comparison
Put two watches side by side at true relative size, from presets or your own measurements.
Bracelet link calculator
How many links to remove for a proper fit, and which side to take them from.
Watch weight calculator
How heavy the same watch is in titanium, steel, gold or platinum.
Owning and maintaining
Water resistance checker
What 30 m, 50 m, 100 m and 200 m genuinely allow, and why the number misleads.
Service interval planner
Whether your watch is actually due for service, based on symptoms rather than the calendar.
Power reserve tracker
When your automatic will stop after you take it off, and when accuracy starts to drop.
Crystal comparison
Sapphire, mineral and acrylic on scratch resistance, shatter resistance and repairability.
Money
Cost of ownership
Purchase price plus servicing, insurance and depreciation, over the years you keep it.
Collection value tracker
Total up your whole collection. Stored privately in your browser, never uploaded.
Reading your watch
More on watches
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Upload a few photos and get model identification, an authenticity verdict and a market valuation in under 30 seconds.
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