Camera memory card compatibility: a 7-point checklist
Check card format, capacity, bus interface, speed class, approved media, firmware, and slot behavior before buying memory for a camera.
1. Start with the physical format
SD, microSD, CFexpress Type A, CFexpress Type B, XQD, and CFast are not interchangeable names. Begin with the slot described in the camera manual. A card that is electronically fast enough is still unusable if the physical format is wrong.
CFexpress needs extra care because Type A, Type B, and Type C use different dimensions. CFexpress Type B shares dimensions and a connector with XQD, but only cameras whose manufacturers added CFexpress support can use both standards.
| Check | Where to verify | What it controls |
|---|---|---|
| Physical format | Camera manual or slot label | Whether the card fits |
| Capacity standard | Supported SDHC, SDXC, or stated maximum | Whether the camera can format and address it |
| Bus interface | UHS-I, UHS-II, or CFexpress support | Potential transfer and buffer-clear speed |
| Speed class | Recording-mode requirements | Whether sustained recording is supported |
| Approved media | Manufacturer support page | Tested card models and capacities |
| Firmware | Camera update notes | Compatibility fixes or added media support |
| Slot behavior | Manual section on dual slots | Backup, overflow, and mode limitations |
2. Confirm capacity and file-system support
For SD media, capacity labels also identify a standard. SDHC covers more than 2GB through 32GB and normally uses FAT32. SDXC covers more than 32GB through 2TB and uses exFAT. A camera designed only for SDHC may not recognize a 64GB or larger SDXC card even though it fits.
A published maximum capacity is a compatibility boundary, not a target. Choose capacity from the expected file sizes and your backup workflow after confirming that the camera supports it. Format new media in the camera rather than assuming a computer-formatted card will behave the same way.
3. Separate the bus interface from the speed class
UHS-I and UHS-II describe the connection between an SD card and its host. Video Speed Class describes an assured minimum sequential write rate. They answer different questions: the bus establishes the available path, while the speed class describes a performance floor under the standard's conditions.
A UHS-II SD card has a second row of contacts and can usually fall back in a UHS-I slot. The camera will still operate at the interface it supports. Paying for a faster bus can improve ingest through a matching reader, but it cannot upgrade the camera slot.
4. Match the exact recording mode
Do not shop by resolution alone. Two 4K modes can use very different bitrates, codecs, frame rates, bit depths, and compression. A card that records ordinary 4K may fail when the camera switches to All-Intra, RAW, high-frame-rate, or simultaneous proxy recording.
Use the media requirement beside the exact menu setting in the manual. V30, V60, and V90 represent minimum write classes of 30, 60, and 90 MB/s. CFexpress cameras may instead publish an approved-card list or a sustained-performance requirement.
5. Check approved cards, firmware, and both slots
Approved-media lists document combinations the camera maker tested. Read capacity and firmware footnotes because one capacity from a card family may be approved while another is not. Recheck the list before a major job; camera and card firmware can change compatibility.
Dual-slot cameras may have unequal slots. Backup recording is limited by the slower card or slot, and certain high-data-rate modes may work only in one slot. Decide whether you need backup, overflow, or separate still and video recording before choosing two cards.
- Test every new card before paid or irreplaceable work.
- Format in camera and verify the highest mode you intend to use.
- Keep a spare card from a tested batch and copy important files promptly.
Frequently asked questions
Can a card be too fast for a camera?
A faster compatible SD card can usually fall back to the camera's supported interface, but the camera will not gain a faster bus. Physical format, capacity support, and the manual still control compatibility.
Why does a card work for photos but stop during video?
Still photos can be buffered and written in bursts. Video requires continuous writing, so the selected recording mode may demand a higher sustained speed class.
Can I use microSD in an SD adapter?
It can work when the microSD card, adapter, and camera meet the required capacity and speed specifications. For demanding professional use, a native full-size card reduces another physical connection in the chain.
Primary references
Technical standards can change. We use the relevant standards organizations as primary references and recommend checking the device maker's current manual.