Is the colour coding really the same for every brand?

Yes. Size number, tab colour and IEC designation are a universal standard rather than a brand choice, so a brown tab means size 312 whoever made the battery. It is one of the genuinely reliable pieces of information in this category and it is why reordering from the colour on the old packet works.

What is the difference between 312 and 13?

They share a diameter of 7.9 millimetres and differ in height: a 312 is 3.6 millimetres tall and a 13 is 5.4. That extra height is where the extra capacity comes from, which is why a 13 lasts roughly twice as long. They are not interchangeable, because a 13 will not close into a 312 compartment.

Why does my device use such a small battery?

Because the device itself is small, and the two are directly linked. A smaller shell has room only for a smaller cell, which is why the least visible devices need their batteries changed most often. If battery life matters more to you than visibility, a larger device with a 13 or a 675 is the trade to make.

Can I use a rechargeable instead?

Only if the device was built for one. Rechargeable hearing aids have a sealed battery and a charging case rather than a door you open, so it is a property of the device rather than a battery you swap in. If handling a cell the size of a shirt button is the difficult part, a rechargeable device is the answer at the next purchase.

How should I store spare batteries?

At room temperature, with the tabs on, away from coins and keys. The old advice to refrigerate them does not help zinc-air chemistry and the condensation can hurt. Leave every tab in place until the moment you need the cell, because air reaching it starts the discharge and replacing the tab does not stop it.

Which hearing aid battery size do I need

Quick answer

Hearing aid batteries come in four sizes and the tab colour is a universal standard: yellow is size 10, brown is 312, orange is 13 and blue is 675. Checking the colour on the packet is the fastest and most reliable way to reorder the right one.

Battery size finder

Published figure This answer is a lookup in a figure published by a named standards body or regulator. We reproduce it, we do not derive it.

Colour is the reliable route. Device style gives the size most commonly fitted to that form and is a starting point rather than an answer, because makers differ.

Enter values above to see the answer.

Equipment this answer points to

Size 10 batteries (yellow)

Energizer

Energizer Hearing Aid Batteries Size 10, 12 pack

$15.25 Published specs

A small yellow pack, which in this size is about two to four weeks of wear for a pair.

Best for: A spare kept in a bag or a car.

Check price on Amazon

Size 312 batteries (brown)

Energizer

Energizer Hearing Aid Batteries Size 312, 24 pack

$15.38 Published specs

A smaller pack for trying a brand without committing to eighty cells, since zinc-air performance does vary a little between makers.

Best for: A first order, or a travel spare.

Check price on Amazon

Size 312 batteries (brown)

Kirkland

Kirkland Signature Hearing Aid Batteries 312, 48 pack

$15.73 Published specs

Mercury free and among the lowest cost per cell available, from a house brand with a long record in this category.

Best for: The lowest running cost on a brown 312 device.

Check price on Amazon

Size 675 batteries (blue)

Duracell

Duracell Hearing Aid Batteries Size 675, 12 count

$15.99 Published specs

A small pack in the largest size, useful as a spare rather than as the main supply.

Best for: A travel spare or a first order.

Check price on Amazon

Common questions

Is the colour coding really the same for every brand?: Yes. Size number, tab colour and IEC designation are a universal standard rather than a brand choice, so a brown tab means size 312 whoever made the battery. It is one of the genuinely reliable pieces of information in this category and it is why reordering from the colour on the old packet works.
What is the difference between 312 and 13?: They share a diameter of 7.9 millimetres and differ in height: a 312 is 3.6 millimetres tall and a 13 is 5.4. That extra height is where the extra capacity comes from, which is why a 13 lasts roughly twice as long. They are not interchangeable, because a 13 will not close into a 312 compartment.
Why does my device use such a small battery?: Because the device itself is small, and the two are directly linked. A smaller shell has room only for a smaller cell, which is why the least visible devices need their batteries changed most often. If battery life matters more to you than visibility, a larger device with a 13 or a 675 is the trade to make.
Can I use a rechargeable instead?: Only if the device was built for one. Rechargeable hearing aids have a sealed battery and a charging case rather than a door you open, so it is a property of the device rather than a battery you swap in. If handling a cell the size of a shirt button is the difficult part, a rechargeable device is the answer at the next purchase.
How should I store spare batteries?: At room temperature, with the tabs on, away from coins and keys. The old advice to refrigerate them does not help zinc-air chemistry and the condensation can hurt. Leave every tab in place until the moment you need the cell, because air reaching it starts the discharge and replacing the tab does not stop it.

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