Varta’s CR2032 batteries don’t come cheap, but their chemistry seems especially robust. Even after nine hours in our LED booklight, the voltage remained at an average 2.99V, and it was only once we’d kept our test pair running for a further three hours that it dipped to 2.75V. While the Panasonics had a higher voltage at the end of the full 12 hours, the Varta cells did a better job of maintaining their nominal 3V voltage over the first nine hour stretch. Like all good things, though, they regularly need replacing, and it makes sense to get the longest-lasting, most reliable CR2032 batteries you can find. We’ve tested a selection from all the major manufacturers, along with some smaller brands, to help you make the right choice.

KEEP OUT OF REACH OF CHILDREN: Swallowing can lead to chemical burns, perforation of soft tissue, and death. Severe burns can occur within 2 hours of ingestion. Seek medical attention immediately. After nine hours in the booklight the voltage had dropped to an average 2.93V, falling to just 2.04V after the full 12 hours, with the voltage of one battery having plummeted to 1.36V. As a result, you’ll probably want to change these sooner than you would if you had bought the Panasonic or Energizer button cells. This is a problem, given that those batteries can be found slightly cheaper, but if you find these in a deal then they’re worth a spin. If you go through a lot of CR2032 batteries, perhaps in LED flashlights or electronic projects, then you might want to buy them in bulk. If so, look no further than GP’s cheap and cheerful bundles. You can have 10 batteries for less than most manufacturers will sell you four, or 30 for around a tenner. Unsurprisingly, they’re not quite as long lasting as rival button cells; even by the nine hour mark our test cells were down to an average 2.91V. By 12 hours that had dropped to just 2.07V, with the LED in our reading light visibly dimmer.They’re a bit too pricey to recommend for devices like a car keyfob, where they’re not in action all the time, but they’re great for wearables and high-drain lights where you want top performance for as long as possible. Third, and most important, these are batteries with staying power. At the nine hour mark they were level with the Duracells, still putting out 2.96V, but by 12 hours they were slightly ahead, at 2.41V. They don’t quite have the consistent output of the Varta cells and fall just behind the Panasonics, while the shelf life is eight years rather than ten. However, if you can’t get your hands on the Panasonic CR2032s, the Energizers are a great second choice. In our LED booklight, they could still deliver a respectable 2.95V output after the initial nine hours of testing, and 2.94V even after the full 12, putting them ahead of every other battery, including those from Duracell and Varta. Punching well about their price point, these are the batteries to buy.

Duracell’s batteries often come with a small price premium, and you’ll spend as much or more on four of these DL2032 cells as you would on six batteries from the competition. Given that, the actual performance in our tests was slightly disappointing. While the voltage after nine hours was high at 2.96V, it had fallen down to 2.28V by the 12 hour mark – below the Varta, Panasonic and Energizer cells. Read next: The best AA and AAA batteries The best CR2032 batteries you can buy in 2023 1. Varta CR2032: The best CR2032 batteries for consistent power