How fast a drive do I need for 4K ProRes?

ProRes 422 HQ at UHD 4K 24 fps is roughly 110 MB/s per stream, so a single SATA SSD handles one or two layers, while multicam or RAW needs NVMe or RAID. Enter your exact format to see it.

Why does my edit stutter even with a fast CPU?

Playback also needs sustained disk throughput. Intra-frame and RAW codecs have very high data rates; if the drive can't sustain codec MB/s × number of streams, you get dropped frames regardless of CPU/GPU.

Disk speed calculator: throughput for video editing

Footage

Format

Resolution

Frame rate

Simultaneous streams

Multicam tracks, picture-in-picture, etc.

Timeline load (VFX / grading)

Heuristic multipliers: layered effects, NR and grading tax the disk beyond the raw codec rate.

Active video layers / nodes

Effects intensity

Typical sustained throughput

Media	~MB/s sustained	Good for
SD UHS-II	250	HD/4K long-GOP capture
HDD 7200 (single)	200–250	Offline proxies, archive
SATA SSD	~530	4K ProRes, light multicam
Thunderbolt 3 SSD	~2500	4K/6K ProRes multicam
NVMe Gen3 / Gen4	3000 / 6500	RAW, 8K, heavy multicam
RAID HDD (8-bay)	~1000	Shared finishing, RAW

Sustained vs burst

Marketing numbers are usually burst (cache) speeds. Editing needs sustained throughput — the speed a drive holds while reading/writing continuously. It's often well below the headline figure, especially on HDDs as they fill.

Disk throughput

Footage

Timeline load (VFX / grading)

Typical sustained throughput