How to choose a memory card: buying guide

Memory cards differ mainly in storage capacity and read speed. A sixty-four gigabyte card suits occasional use, while models with several hundred gigabytes meet the needs of photographers and videographers. Transfer speed determines fluidity during recording and playback.

What to check

Selecting the right capacity Capacity indicates the volume of data the card can hold. It ranges from sixty-four gigabytes for entry-level models to over one thousand gigabytes for the most generous versions. On Kalyneo, the capacity rating compares available space: the longer the bar, the more photos, videos or files you can store. A two hundred and fifty-six gigabyte card corresponds to the current market median and suits most digital cameras and action cams. Higher capacities target users who record in high definition or prefer to avoid frequent transfers. Market median: 256 GB

Assessing read speed Read speed, expressed in megabytes per second, influences the time needed to copy files to a computer or display burst images. The slowest cards reach one hundred megabytes per second, while the fastest exceed eight hundred megabytes per second. The Kalyneo rating reflects this performance: an extended bar signals accelerated reading. The median stands at one hundred and eighty megabytes per second, a throughput sufficient for everyday photography. High speeds become useful when processing large image series or maximum resolution videos, where every transfer second counts. Market median: 180 MB/s

Compatibility and format Check that the card format matches your device slot: some only accept compact cards, others larger formats. Adapters sometimes allow using a small format card in a standard reader, but direct compatibility is preferable to avoid any disconnection risk. Consult your equipment manual or manufacturer specifications before purchase. An incompatible card simply cannot be inserted or will not be recognised, making its use impossible.

Benchmarks based on 30 recent market listings, collected on 4 October 2026.

What you get for each budget

Under €15

Cards under fifteen euros offer limited capacities and modest read speeds, suitable for document storage or occasional smartphone use.

€15 to €50

Between fifteen and fifty euros, you access intermediate capacities and comfortable read rates, sufficient for amateur photography and standard definition video recording.

Over €50

Above fifty euros, cards combine vast capacities and high read speeds, meeting the demands of professionals and high-resolution content creators.

Frequent mistakes

Buying a low-capacity card to save a few euros, then having to replace it quickly as needs grow.

Neglecting read speed by only looking at price, which considerably slows down large file transfers.

Confusing read speed with write speed, two distinct values of which only the former is rated here.

Choosing excessive capacity relative to actual use, tying up budget that could have improved other equipment.