What battery does a calculator use?
Most calculators take an LR44 (1.5 V alkaline button cell). Some use CR2032, CR2025 or AAA instead. The battery cover is on the back; the code is printed on the cover or on the old cell.
| Battery | How common | Size | Volts | Capacity |
|---|---|---|---|---|
| LR44 | Most common | 11.6 mm × 5.4 mm | 1.5 V | ≈ 120 mAh |
| CR2032 | Also used | 20 mm × 3.2 mm | 3 V | ≈ 225 mAh |
| CR2025 | Also used | 20 mm × 2.5 mm | 3 V | ≈ 165 mAh |
| AAA | Also used | 10.5 mm × 44.5 mm | 1.5 V | ≈ 1,150 mAh |
Calculator battery: what to know
- Many basic and scientific calculators use one or two LR44 (AG13) button cells, often alongside a solar panel.
- Thin calculators commonly use a CR2032 or CR2025.
- Graphing calculators usually take four AAA batteries, plus a small backup cell in some models.
How to check which battery your calculator takes
The battery cover is on the back; the code is printed on the cover or on the old cell. 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 LR44 page for safe swaps.
AAA: NiMH rechargeable AAA (HR03) is 1.2 V and 800–1,100 mAh. Lithium AAA (FR03) lasts longer in cold and high-drain use.