Ratekeeper reveals exactly how your watch runs, measured against atomic time, to a tenth of a second a day. No special gear. Just a tap.
Free to measure one watch. One purchase for the rest.
iPhone, iPad, and Android.
Set your watch to true time. A day later, tap the moment the second hand hits twelve, and Ratekeeper does the rest, comparing your tap to atomic time and working out the exact rate.
Every time you reset the watch, a new run begins, and all your readings chart together. Watch a rate settle after a service, drift as it comes due, or measure up to a precision standard.
Manual, automatic, or quartz: every watch is measured on its own terms, with its own history and its own breakdown by position.
Install it and start measuring. One purchase, never a subscription, opens the full record and the rest of your collection.