Batteries

CR2025 vs CR2032: same diameter and voltage, different thickness

These two lithium coin cells look nearly identical from above. Manufacturer datasheets show the important difference: CR2025 is 2.5 mm thick, while CR2032 is 3.2 mm thick.

Quick answerBoth examples are nominally 20.0 mm in diameter and 3.0 V. CR2025 is nominally 2.5 mm thick; CR2032 is 3.2 mm thick. Capacity also differs by manufacturer and test conditions, with CR2032 typically specified higher.
Example specificationCR2025CR2032
Nominal voltage3.0 V3.0 V
Nominal diameter20.0 mm20.0 mm
Nominal height/thickness2.5 mm3.2 mm
Murata nominal capacity example160 mAh220 mAh
Murata standard discharge-current example0.2 mA0.2 mA

Capacity figures are manufacturer/test-condition specific. They are useful for comparison within the cited datasheets, not as a universal guaranteed runtime.

What the numbers tell you

For these common CR coin cells, the numeric part lines up with the nominal physical dimensions shown in manufacturer datasheets. CR2032 is approximately 20 mm in diameter and 3.2 mm high. CR2025 is approximately 20 mm in diameter and 2.5 mm high.

That makes the naming easier to remember, but it does not make similarly named cells automatically interchangeable. Physical size is only one compatibility condition.

Why the thicker CR2032 often stores more energy

The two cells share the same nominal diameter and voltage, but the CR2032 has more internal volume because it is thicker. In Murata's standard product data, the cited CR2025 is rated at 160 mAh while the cited CR2032 is rated at 220 mAh under the manufacturer's stated conditions.

Energizer datasheets show the same general pattern but different absolute capacity figures, which is a useful reminder: capacity is not encoded as a fixed universal value in the model name. Chemistry implementation, test load, temperature, cutoff voltage, and manufacturer design all matter.

Can you replace one with the other?

Do not make that decision from voltage alone. The correct question is whether the device manufacturer permits the substitute and whether the holder is designed for the alternate thickness.

A CR2032 is 0.7 mm thicker than a CR2025. In a holder designed around the thinner cell, the thicker battery may not fit correctly or may place inappropriate mechanical force on contacts or covers. In the opposite direction, a thinner cell may fit loosely or fail to maintain reliable contact in a holder designed for a thicker cell.

Compatibility ruleUse the battery type specified by the device manufacturer. Matching nominal voltage does not override mechanical fit, contact pressure, discharge requirements, temperature range, or application restrictions.

Why capacity numbers vary across brands

Battery capacity is measured under a defined test. For example, a datasheet may specify a particular load, temperature, and cutoff voltage. Change those conditions and the usable capacity can change.

That is why a table copied from one brand should not be treated as the exact runtime specification for every battery carrying the same IEC-style designation. For a product comparison, use the datasheet for the exact manufacturer and model.

Application restrictions matter too

Manufacturer datasheets can include application limitations beyond physical size. Murata's standard CR2032 documentation, for example, distinguishes ordinary consumer equipment from certain automotive and higher-class medical applications. The correct battery choice therefore depends on the device and environment, not merely the printed dimensions.

Coin-cell safety is not optional

Lithium coin cells are small enough to be swallowed and manufacturer warnings emphasize that ingestion can cause severe injury. Keep loose cells away from children, store them securely, and follow the battery and device manufacturer's safety instructions.

A simple comparison checklist

  1. Read the exact battery designation specified on the device, manual, or existing cell.
  2. Match chemistry/designation rather than relying on diameter alone.
  3. Check nominal voltage.
  4. Check diameter and thickness.
  5. For demanding applications, check discharge and temperature requirements in the datasheet.
  6. Prefer the exact type required by the device manufacturer instead of improvising around holder fit.

Related battery guides

Primary sources

Bottom line

CR2025 and CR2032 share a 20 mm nominal diameter and 3 V nominal voltage, but they are not the same physical battery. The 0.7 mm thickness difference is real, and capacity plus application requirements can differ too. Match the device specification first.