🔋 Battery Size Chart
Dimensions (diameter × height in mm), voltage, and IEC designations for every common battery size — AA, AAA, C, D, and 9V cells, plus button and coin cells and cylindrical lithium-ion packs. Coin and button cell names encode their size: a CR2032 is 20 mm across and 3.2 mm thick.
Standard Household Batteries
| Size | IEC Name | Dimensions (∅ × H) | Voltage | Typical Uses |
|---|---|---|---|---|
| AAA | LR03 | 10.5 × 44.5 mm | 1.5 V | Remotes, small electronics |
| AA | LR6 | 14.5 × 50.5 mm | 1.5 V | Toys, clocks, wireless mice |
| AAAA | LR8D425 | 8.3 × 42.5 mm | 1.5 V | Styluses, glucose meters |
| C | LR14 | 26.2 × 50.0 mm | 1.5 V | Flashlights, portable radios |
| D | LR20 | 34.2 × 61.5 mm | 1.5 V | Lanterns, large flashlights |
| 9V | 6LR61 | 26.5 × 17.5 × 48.5 mm | 9 V | Smoke alarms, multimeters |
Alkaline cells deliver 1.5 V; rechargeable NiMH versions of the same sizes deliver 1.2 V, which most devices tolerate.
Button & Coin Cells
| Size | Dimensions (∅ × H) | Voltage | Typical Uses |
|---|---|---|---|
| CR2032 | 20.0 × 3.2 mm | 3 V | Car key fobs, motherboards, scales |
| CR2025 | 20.0 × 2.5 mm | 3 V | Key fobs, small remotes |
| CR2016 | 20.0 × 1.6 mm | 3 V | Watches, calculators |
| CR1632 | 16.0 × 3.2 mm | 3 V | Tire pressure sensors, fobs |
| CR123A | 17.0 × 34.5 mm | 3 V | Security sensors, cameras |
| LR44 | 11.6 × 5.4 mm | 1.5 V | Thermometers, laser pointers |
| A23 | 10.3 × 28.5 mm | 12 V | Garage remotes, doorbells |
CR = 3 V lithium chemistry; LR = 1.5 V alkaline. Keep coin cells away from children — swallowing one is a medical emergency.
Cylindrical Lithium-Ion Cells
| Size | Dimensions (∅ × H) | Voltage | Typical Uses |
|---|---|---|---|
| 18650 | 18.6 × 65.2 mm | 3.6–3.7 V | Flashlights, laptop packs, power tools |
| 21700 | 21.0 × 70.0 mm | 3.6–3.7 V | EVs, high-drain flashlights |
| 14500 | 14.0 × 50.0 mm | 3.6–3.7 V | AA-size lithium — NOT interchangeable with AA |
Named for their dimensions: an 18650 is ~18 mm in diameter and 65 mm long. Capacities for quality 18650 cells run 2,500–3,500 mAh.
Coin Cell Equivalents & Alternate Names
The same physical cell is sold under several brand and standard codes. Any code in a row fits the same devices.
| Common Name | Also Sold As | Size · Voltage |
|---|---|---|
| CR2032 | DL2032, ECR2032, BR2032, KCR2032 | 20 × 3.2 mm · 3 V lithium |
| CR2025 | DL2025, BR2025, ECR2025 | 20 × 2.5 mm · 3 V lithium |
| CR2016 | DL2016, BR2016, ECR2016 | 20 × 1.6 mm · 3 V lithium |
| LR44 | AG13, A76, L1154 · silver: SR44 / 357 / 303 | 11.6 × 5.4 mm · 1.5 V |
| A23 | 23A, MN21, V23GA, LRV08 | 10.3 × 28.5 mm · 12 V |
| CR123A | CR17345, 123 | 17 × 34.5 mm · 3 V lithium |
Silver-oxide cells (SR / “357”) match the alkaline LR equivalents in size but hold a steadier 1.55 V and usually last longer.
Other Names for Common Batteries
Informal and regional names people use, mapped to the standard size.
| You Might Call It | Standard Size |
|---|---|
| A · “single A” · “A size” | Usually means AA. A true A cell (17 × 50 mm) exists but is rare in consumer gear. |
| No. 5 / “number 5” | AA — the Chinese (号) naming system, where No. 5 = AA. |
| No. 7 | AAA (Chinese naming). |
| Penlight battery | AA. |
| Torch battery (UK) | Usually C or D — the cells in a handheld flashlight. |
| Square / PP3 / 9-volt | 9V (IEC 6LR61). |
| Button / coin / watch / “circle” battery | Coin cells — the CR/LR/SR series (CR2032, LR44, …). |
| Short fat battery | Typically a C or D cell. |
Frequently Asked Questions
What are the most common button and coin cell battery sizes?
The most common are the CR2032 (20 × 3.2 mm), CR2025 (20 × 2.5 mm), and CR2016 (20 × 1.6 mm) 3-volt lithium cells, plus the 1.5-volt LR44 (11.6 × 5.4 mm) alkaline button cell. In a CR/LR number, the first two digits are the diameter in millimeters and the last two are the height in tenths of a millimeter.
What battery is equivalent to an LR44?
An LR44 is interchangeable with the AG13, A76, and L1154 (all 1.5 V alkaline). The silver-oxide SR44 — also sold as 357 or 303 — is the same size and fits the same devices, but holds a steadier 1.55 V and tends to last longer.
Is a CR2032 interchangeable with a CR2025 or CR2016?
All three are 20 mm across and 3 V, so they fit the same holder. They differ only in thickness (3.2, 2.5, and 1.6 mm) — a thicker cell holds more capacity. A thinner cell may rattle or lose contact, and a thicker one may not physically fit, so use the size the device specifies when you can.
What is the difference between CR and LR batteries?
CR cells are 3-volt lithium; LR cells are 1.5-volt alkaline. They are not interchangeable — swapping an LR for a CR (or the reverse) feeds the device the wrong voltage. Match the letter prefix, not just the number.
What is the diameter of a D battery?
A D cell is 34.2 mm in diameter and 61.5 mm tall. For comparison, a C cell is 26.2 mm, an AA is 14.5 mm, and an AAA is 10.5 mm in diameter — all are 1.5 V.
What are the smallest and largest common battery sizes?
Among standard cylindrical cells, the AAAA (8.3 mm diameter) is the smallest and the D (34.2 mm) is the largest; coin cells are smaller still. Higher-capacity lithium-ion cells such as the 18650 and 21700 are the large cells used in power tools, laptops, and EVs.