AA vs AAA Battery: Complete Size, Voltage & Usage Comparison

Same 1.5V, very different capacity and devices. Here is how to choose between AA and AAA without guessing.

AA (LR6/R6) and AAA (LR03/R03) are both 1.5V cells. The difference is size: AA is 14.5 mm in diameter and 50.5 mm long, with roughly 2,000–3,000 mAh; AAA is 10.5 mm and 44.5 mm with roughly 800–1,200 mAh. Plainly: same voltage, about twice the capacity in AA.

AA is the go-to cell for medium-high drain devices — torches, toys, gaming controllers, wireless cameras. AAA fits slim devices — TV remotes, smoke detectors, wall clocks, small torches.

If a device accepts both sizes (many toy and lantern lines use adapters), choose AA for longer runtime. Never force AAA where AA is intended: lower capacity and poor contact.

When buying in volume, both sizes come in bulk shrink packs (2/4/8/16 pcs) or full paper packs — we can supply both under your brand with custom packaging.