How much storage will your footage need?

It depends on the bitrate, not just the resolution. Multiply the bitrate in Mbps by 0.45 to get gigabytes per hour. A 100 Mbps 4K file is about 45 GB an hour, a 600 Mbps all-intra file is about 270 GB an hour, and 4K ProRes 422 HQ at 29.97p (884 Mbps) is about 398 GB an hour.

Pick your camera and recording mode above, then look at the card table. It shows how long each card size records in that mode. Most people want a card that covers their longest shoot without swapping, plus a spare.

The card has to write at least as fast as the camera records. V30 cards are rated for 30 MB/s (240 Mbps), V60 for 60 MB/s (480 Mbps) and V90 for 90 MB/s (720 Mbps). Faster modes need CFexpress. If your camera manual lists a required card for a mode, follow the manual.

The bitrates come from each manufacturer's own specifications and manuals (checked November 11, 2026), and the math is exact. Real files can differ by a few percent because of the audio track, file overhead and how the card is formatted, so results are accurate to within about 5%. RAW formats like Blackmagic RAW and ProRes RAW change size with the image, so treat those as estimates.

Cameras compress video in different ways. All-intra formats (like XAVC S-I, ALL-I or ProRes) save every frame on its own, which is easier to edit but uses much more space. Long-GOP formats (like XAVC S, IPB or H.265) save changes between frames and are far smaller. Higher frame rates also use more data.