Magnets erase your phone or cards easily
Modern smartphones use flash memory for data storage, which is not affected by ordinary consumer magnets the way older magnetic storage media like floppy disks and cassette tapes were, though very powerful specialized magnets can still interfere with certain phone hardware components like compasses or, in some models, disable magnetically triggered features.
What we know
The belief that magnets can erase a smartphone's data or damage the device originates from a period when magnetic storage media, including floppy disks, magnetic tape, and early hard disk drives, stored data by magnetizing tiny regions of a physical medium, making them genuinely vulnerable to data loss or corruption from exposure to a sufficiently strong external magnetic field, since a strong magnet could alter or scramble those magnetized regions. This was a real and well documented risk for those older storage technologies throughout the 20th century.
Modern smartphones do not use magnetic storage for their primary data storage. Instead, they use flash memory, commonly NAND flash, which stores data by trapping electrical charge within transistor cells rather than through magnetization of a physical medium, a fundamentally different storage mechanism that is not affected by ordinary magnetic fields in the way magnetic storage media were. This means the everyday magnets found in household items, including refrigerator magnets, magnetic phone mounts, magnetic clasps on bags or cases, and typical craft or toy magnets, pose no realistic risk of erasing data from a modern smartphone's flash storage, a point confirmed by Apple's own published support documentation addressing this exact question.
Some remaining nuance exists around specific hardware components rather than data storage broadly. Smartphones contain a magnetometer, the sensor used for the device's digital compass function within mapping and navigation apps, and exposure to a very strong magnet can temporarily interfere with or produce inaccurate readings from this specific sensor while the magnet remains in close proximity, though this effect is temporary and resolves once the magnetic interference is removed, rather than causing any permanent damage or affecting stored data.
Apple's introduction of MagSafe technology, beginning with iPhone 12 in 2020, added an intentional array of magnets built into the phone itself, designed to enable magnetic wireless charging and accessory attachment, and Apple's own documentation for MagSafe-equipped iPhones specifically advises keeping certain items with magnetic stripes, such as some hotel key cards, credit cards with magnetic stripes, and passports with embedded chips, at a safe distance from the phone's magnets, since these specific items, which do rely on magnetic storage or sensitive embedded electronics, could genuinely be affected by close and prolonged proximity to the phone's built-in magnets, a caution that is about protecting those separate magnetic-stripe items rather than any risk to the phone's own data.
Extremely powerful specialized magnets, well beyond typical consumer strength, such as those used in certain industrial or scientific settings, could theoretically cause physical or electronic damage to a phone through mechanisms other than data erasure, but this scenario is far removed from ordinary consumer exposure to household or accessory magnets. For virtually all everyday situations, including magnetic phone mounts in cars, magnetic wallet cases, and MagSafe accessories, the practical risk of magnets erasing a modern smartphone's data is effectively nonexistent, a legacy misconception carried over from an earlier era of genuinely magnetic storage technology that smartphones no longer use.
Common claims
- A fridge magnet can erase your phone's memoryFalse. Smartphones use NAND flash storage, which is completely immune to magnetic fields.
- Magnetic phone cases will erase your credit cardVery unlikely. HiCo magnetic stripes require approximately 4,000 gauss to erase; most consumer magnets produce far less.
- EMV chip cards can be erased by magnetsFalse. EMV chips are integrated circuits with no magnetic storage element.