Home › By device › Watch

What battery does a wrist watch use?

Most wrist watches take an SR626SW (1.55 V silver oxide button cell). Some use SR621SW, SR920SW, CR2032, CR2025 or CR2016 instead. Open the case back (snap-off or screw-down) and read the code on the old cell; some case backs also list it.

BatteryHow commonSizeVoltsCapacity
SR626SWMost common6.8 mm × 2.6 mm1.55 V≈ 28 mAh
SR621SWAlso used6.8 mm × 2.15 mm1.55 V≈ 23 mAh
SR920SWAlso used9.5 mm × 2.05 mm1.55 V≈ 40 mAh
CR2032Also used20 mm × 3.2 mm3 V≈ 225 mAh
CR2025Also used20 mm × 2.5 mm3 V≈ 165 mAh
CR2016Also used20 mm × 1.6 mm3 V≈ 90 mAh
SR626SW⌀6.8 × 2.6 mmSR621SW⌀6.8 × 2.15 mmSR920SW⌀9.5 × 2.05 mm
The 3 batteries above drawn to the same scale.

Watch battery: what to know

How to check which battery your wrist watch takes

Open the case back (snap-off or screw-down) and read the code on the old cell; some case backs also list it. Battery codes are printed on the flat face of coin and button cells and along the side of AA, AAA and 9V batteries. Match the code exactly: a cell that looks similar can be a different thickness or voltage; see the SR626SW page for safe swaps.