Hearing aid battery sizes, colours and specs
Quick answer
Hearing aid batteries come in four standard zinc-air sizes, identified by both a number and a colour: size 10 (yellow, 5.8 by 3.6 mm), size 312 (brown, 7.9 by 3.6 mm), size 13 (orange, 7.9 by 5.4 mm) and size 675 (blue, 11.6 by 5.4 mm). All four share a nominal 1.45 volt output and are activated by air once the protective tab is removed.
Size number, tab colour and IEC designation are a genuine worldwide standard: a size 13 battery is orange on every brand's packaging, everywhere it is sold, which makes colour the fastest way to identify the right one without reading fine print. Dimensions and voltage are equally fixed across brands, because a battery has to physically fit a standardised compartment.
Capacity and typical life are a different kind of figure. They are not set by any standards body, and they vary by brand, by how hard a specific hearing aid is working, and by how much audio is streamed from a phone. The ranges below are the trade convention for what to expect, not a guaranteed run time for any specific device.
Battery basics: the same for every size
Every standard size uses the same 1.45 volt zinc-air chemistry and the same tab-activation method.
| Property | Value |
|---|---|
| Chemistry | Zinc-air |
| Nominal voltage | 1.45 V |
| Activation | Air-activated: pull the tab, then wait about a minute before closing the battery door. |
| Tab handling | Leave the tab in place until the battery is actually needed; once removed it cannot be reapplied to pause activation. |
Size, colour and dimensions
Every maker uses the same tab colour for the same size, which is why colour, not the printed number, is the fastest way to check a battery at a glance.
| Size | Colour | IEC designation | Diameter (mm) | Height (mm) |
|---|---|---|---|---|
| Size 10 | Yellow | PR70 | 5.8 | 3.6 |
| Size 312 | Brown | PR41 | 7.9 | 3.6 |
| Size 13 | Orange | PR48 | 7.9 | 5.4 |
| Size 675 | Blue | PR44 | 11.6 | 5.4 |
Typical life and which devices use each size
Size 675, the largest and highest-capacity size, typically lasts 9 to 20 days, while size 10, the smallest, typically lasts only 3 to 7 days.
| Size | Colour | Capacity (mAh) | Typical life | Typical devices |
|---|---|---|---|---|
| Size 10 | Yellow | 90 to 100 mAh | 3 to 7 days | The smallest completely in canal and in the canal devices, and small receiver in canal aids. |
| Size 312 | Brown | 160 to 180 mAh | 3 to 10 days | The most common size by a wide margin. Most receiver in canal and many in the ear devices, such as Rayovac Size 312 Extra Advanced, 80 count. |
| Size 13 | Orange | 280 to 310 mAh | 6 to 14 days | Behind the ear devices and larger in the ear devices, such as Duracell Hearing Aid Batteries Size 13, 60 count. |
| Size 675 | Blue | 600 to 650 mAh | 9 to 20 days | High power behind the ear devices, and the cochlear implant variant of this size, such as Duracell Hearing Aid Batteries Size 675, 12 count. |
Common questions
- What colour is a size 13 hearing aid battery?
- Orange. This is a worldwide standard, not a brand choice, so a size 13 battery from any manufacturer, in any country, carries the same orange tab, marked with the IEC designation PR48. Size 13 batteries measure 7.9 by 5.4 mm and are typically used in behind the ear devices and larger in the ear devices that draw more current.
- How long does a hearing aid battery typically last?
- It depends on the size. Size 10, the smallest, typically lasts 3 to 7 days. Size 312, the most common size, typically lasts 3 to 10 days. Size 13 typically lasts 6 to 14 days, and size 675, the largest and highest-capacity, typically lasts 9 to 20 days. These are trade convention ranges, not guarantees, since real life depends on how much amplification and streaming the device does.
- Are all size 312 batteries interchangeable between brands?
- Yes, for the battery itself. Size, colour and IEC designation (PR41 for size 312) are a genuine worldwide standard, so a size 312 from any brand physically fits any device built for size 312. What is not interchangeable between brands is a receiver or dome part number, which is set individually by each hearing aid manufacturer.
- Why do hearing aid batteries have a tab on them?
- They use zinc-air chemistry, which needs exposure to air to activate. The tab seals out air during storage so the battery does not slowly discharge on a shelf. Once the tab is removed, air reaches the cell and it begins working, which is also why leaving the tab off, or the battery drawer open, when a device is not in use shortens its life.
- What is the difference between size 10 and size 13 batteries?
- Size 10 is smaller (5.8 by 3.6 mm, yellow tab) and typically lasts 3 to 7 days; it is used in the smallest completely in canal and in the canal devices. Size 13 is larger (7.9 by 5.4 mm, orange tab) and typically lasts 6 to 14 days; it is used in behind the ear devices and larger in the ear devices that draw more power.
- Can I use a size 675 battery in a device made for size 13?
- No. Even though both are zinc-air cells at the same 1.45 volt nominal voltage, size 675 (11.6 by 5.4 mm) is physically larger than size 13 (7.9 by 5.4 mm) and will not fit a compartment sized for size 13. Each device is designed around one specific battery size, and the compartment itself will not accept the wrong one.
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Last updated 2026-09-17.