Which microSD do you actually need? Start with the job.
Speed badges sell cards; the workload decides which one survives. Pick your use case below for the right grade and speed class — and skip the ratings you're being upsold.
These cameras overwrite around the clock. A consumer card wears out in months and fails silently — you find out when the footage isn't there. Endurance, not speed badges, is what keeps it recording.
- Endurance (TBW / P/E) — the number that decides months vs. years
- V30 / U3 sustained write for steady 4K
- Do not select on A2 alone — match Video Speed Class and endurance to the camera
- −25 ~ 85°C if it lives in a hot car or outdoors
Light, occasional writes — so capacity and value matter more than endurance. This is the one place the A1/A2 app-performance rating actually earns its keep, because the card runs apps and loads files.
- Capacity first — pick the size you actually need
- A1 / A2 does help here (app launch, random reads)
- U3 / V30 only if you shoot 4K on the device
- Verify real capacity on cheap high-capacity cards
Short, intense high-bitrate bursts need sustained write headroom, not just a fast label. Counterfeit and over-spec'd cards are rampant here — and the footage you lose is unrepeatable, so verify capacity before the shoot.
- V30 / U3 minimum; V60 / V90 for high-bitrate 4K/8K
- Sustained write speed > peak — that's what avoids dropped frames
- Verify true capacity with H2testw (fakes are common)
- Enough endurance for long continuous sessions
B2B wholesale — distributors, resellers and OEMs. Recommendations are general guidance; tell us the device and volume for a spec'd quote.