357 and LR44 batteries are the same thing, just with different names

A 357 battery and an LR44 battery are identical. They are the same physical battery with two different naming systems. The "357" name comes from the IEC (International Electrotechnical Commission) standard, while "LR44" is the ANSI (American National Standards Institute) designation. You will see both names on packaging, and either one will work in any device that calls for the other.

Both names refer to a small, round silver-oxide or alkaline button cell that measures 11.6 millimeters in diameter and 5.4 millimeters in thickness. These batteries power watches, calculators, hearing aids, laser pointers, small toys, and medical devices. Because they are so common and inexpensive, they are sold everywhere — drugstores, supermarkets, hardware stores, and online retailers all stock them under one name or both.

Key Takeaways

  • 357 and LR44 are the same battery sold under two different naming standards — IEC and ANSI respectively.
  • Both batteries are 11.6 mm in diameter and 5.4 mm thick, and they have identical voltage and capacity.
  • You can use a 357 in any device that asks for an LR44, and vice versa, with no modification needed.
  • Silver-oxide 357/LR44 batteries last longer than alkaline versions but cost slightly more.
  • Check your device's manual or battery compartment label to confirm the voltage requirement before buying, since some devices need different button cells.

Why the same battery has two names

Battery naming standards differ by region and industry. The IEC standard, used mainly in Europe and internationally, assigns numbers like 357. The ANSI standard, used in North America, assigns codes like LR44. Manufacturers and retailers use whichever standard applies to their market, so the same battery gets labeled both ways depending on where you buy it.

This dual naming happens with many button cell batteries. A 303 battery is the same as an LR44, a 364 is the same as an SR621, and so on. The chemistry and dimensions are identical — only the label changes. When you are shopping, you can use either name to find what you need.

Voltage and chemistry: alkaline versus silver-oxide

Both 357 and LR44 batteries come in two main types: alkaline and silver-oxide. Both types deliver 1.5 volts, so they are electrically interchangeable in most devices. The difference is in how long they last and what they cost.

Alkaline 357/LR44 batteries are cheaper and work well for low-drain devices like watches and calculators. Silver-oxide versions cost more but hold their voltage more steadily over time and last longer in devices that draw power continuously. Hearing aids, for example, often specify silver-oxide because the steady voltage matters for sound quality. Check your device's manual or the label inside the battery compartment to see which type is recommended.

How to tell which battery your device needs

The easiest way is to look inside the battery compartment. Most devices have a label printed on the inside of the battery door or on the compartment itself. It will say "357" or "LR44" or sometimes both. If the label is worn away, check the device's manual or the manufacturer's website.

If you cannot find the label, you can also look at the battery that is already in the device. Remove it carefully and read the number printed on the top. That is the battery you need to replace. Take it with you to the store if you are unsure, or take a photo of the number.

Where to buy 357 and LR44 batteries

These batteries are sold almost everywhere. Drugstores like CVS and Walgreens stock them in the health and beauty section or near the checkout. Supermarkets carry them in the pharmacy or household goods aisle. Hardware stores like Home Depot and Lowe's have them in the electrical section. Online retailers like Amazon sell them in bulk or single packs.

Prices vary by brand and quantity. A single battery at a drugstore might cost $3 to $5, while a pack of 10 from an online retailer might cost $8 to $12 total. Buying in bulk is cheaper per battery if you use them regularly. Store brands are usually the same quality as name brands at a lower price.

Common devices that use 357 and LR44 batteries

Watches are the most common use — both digital and analog watches with small movements often run on a single 357/LR44. Calculators, especially small pocket calculators, use them. Hearing aids use them frequently, and they are the standard battery for most over-the-counter hearing aid models. Laser pointers, small flashlights, and electronic scales also use them.

Some medical devices like glucose meters and blood pressure monitors use 357/LR44 batteries. Small electronic toys, key fobs, and remote controls sometimes use them too. If you have a small electronic device and are not sure what battery it takes, the battery compartment label is your best guide.

What to do if you cannot find a 357 or LR44

If a store is out of stock, you have a few options. First, check if the store can order it for you — most retailers can get button cell batteries within a day or two. Second, try a different store type: if the drugstore is out, try a supermarket or hardware store. Third, order online for delivery or in-store pickup.

Do not substitute a different battery size or voltage unless you are certain it will work. Using the wrong battery can damage the device or cause it to malfunction. If you are stuck without the right battery, contact the device manufacturer to ask what alternatives are safe.

Frequently Asked Questions

Can I use a 357 battery in a device that says LR44?

Yes. They are the same battery with different names. A 357 will work perfectly in any device labeled for LR44, and vice versa. No modification is needed.

How long does a 357 or LR44 battery last?

It depends on the device and the battery type. In a watch, a single 357/LR44 can last one to three years. In a hearing aid, which draws power continuously, it might last three to seven days. Alkaline versions typically last shorter than silver-oxide in the same device.

Is there a difference between a 357 and a 357A battery?

A 357A is a silver-oxide version, while a plain 357 is usually alkaline. Both are the same size and voltage, but the 357A lasts longer. Check your device's manual to see which type is recommended.

What should I do with old 357 or LR44 batteries?

Button cell batteries contain mercury or other metals in some cases and should not go in the trash. Take them to a battery recycling program. Many retailers like Best Buy and Home Depot have battery recycling bins near the entrance. Your local waste management website can also direct you to a drop-off location.

Are 357 and 303 batteries the same?

Yes. A 303 is the IEC name and LR44 is the ANSI name for the same battery. You may also see it called a 357 or SR44. All four names refer to the identical battery.