3 hours of 4K ProRes 422 HQ
ProRes 422 HQ, UHD 4K, 30 fps, about 707 Mbps.
Result: about 954 GB before margin, or 1.05 TB with a 10% buffer. Use a 2 TB SSD for room to offload and verify.
Video File Size & Footage Storage Calculator
Calculator inputs
Mode
Preset bitrate:
hr
min
sec
GB
Mbps
Optional: set your own bitrate; it overrides the selected preset.
Results
0 GBEstimated storage with margin
0 GBDecimal GB
0 GiBBinary GiB
0 TBDecimal TB
0 MB/sRequired write speed
0 GB/minStorage per minute
0 GB/hrStorage per hour
0 cards256 GB card estimate
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Grouped codec preset library
Rates are planning values. Labels identify published constant rates, target bitrates, maximum bitrates, or approximate VBR camera settings.
| Family | Preset | Resolution | Frame rate | Bitrate | Basis |
|---|
Worked examples
1 hour of 4K H.265
HEVC/H.265, UHD 4K, 30 fps, about 25 Mbps target VBR.
Result: about 11.3 GB before margin, or 12.4 GB with a 10% buffer. A 128 GB card can hold many short takes.
90 minutes of 1080p H.264
H.264, 1080p, 30 fps, about 12 Mbps target VBR.
Result: about 8.1 GB before margin, or 8.9 GB with a 10% buffer. A 32 GB card is usually enough for one copy.
How much 256 GB or 1 TB holds
At 707 Mbps ProRes 422 HQ with a 10% margin, a 256 GB card holds about 43 minutes, while a 1 TB SSD holds about 2.9 hours.
Recommendation: plan one extra card or drive when recording long interviews, proxies, or dual-system audio.
How to use this calculator
Planning storage for video shoots and edits can be tricky because resolution, codec, compression mode, frame rate, and bitrate all change file size. Use duration mode when you know how long the shoot is. Use capacity mode when you need to know how long a 128 GB card, 256 GB card, 512 GB card, 1 TB SSD, or custom drive can record.
Step-by-step
- Choose storage from duration or record time from capacity.
- Select resolution, frame rate, codec family, and a preset, or enter a custom Mbps value.
- Set duration or available media capacity, then choose a safety margin.
- Review decimal GB/TB, binary GiB, write speed, per-minute and per-hour usage, and card count.
If you are capturing multiple formats at once, such as camera originals and proxy files, run the calculator twice and add the totals together. Separate audio is usually small compared with video, but multi-track audio, sidecar files, thumbnails, proxies, and file-system overhead are good reasons to keep a 10% to 20% buffer.
Formula
file size = bitrate × duration ÷ 8
GB = bytes ÷ 1,000,000,000; GiB = bytes ÷ 1,073,741,824
Mbps means megabits per second. MB/s means megabytes per second. Divide Mbps by 8 to get MB/s. Variable-bitrate codecs such as H.264, H.265, BRAW, and REDCODE can differ from the estimate because motion, detail, ISO noise, encoder settings, and maximum bitrate limits change the actual data rate.
Methodology and sources
Last reviewed: 23 June 2026. Published or vendor-derived rates are used where practical, including Apple ProRes data-rate guidance, Avid DNxHD/DNxHR documentation, Digital Cinema Package JPEG 2000 limits, and camera-format guidance from manufacturers such as Blackmagic Design and RED. H.264 and HEVC presets are target or approximate VBR planning values based on common camera and platform bitrate guidance, not guaranteed file sizes.
The calculator treats preset rates as megabits per second, multiplies by duration, and applies the selected safety margin after the base file-size calculation. Uncompressed RGB/YUV rates are calculated from resolution, frame rate, chroma sampling, and bit depth assumptions, so they scale directly when you change those controls.
Source references: Apple ProRes support and data-rate guidance, Avid DNxHR codec bandwidth specifications, DCI digital cinema specifications, Blackmagic RAW overview, and REDCODE RAW overview.
5 quick facts about footage storage
ProRes HQ is hefty
At 4K/30p, ProRes 422 HQ sits around 707 Mbps—roughly 318 GB per hour of footage.
~318 GB/hr
Frame rate doubles size
Going from 30p to 60p often doubles bitrate for intra codecs, so storage needs can jump 2×.
30p → 60p
HEVC saves space
H.265/HEVC can cut storage roughly in half versus H.264 at similar perceptual quality.
Efficiency
Audio is tiny
Stereo 48 kHz/24-bit PCM adds about 2.3 Mbps—small compared to video, but worth adding to totals.
+2.3 Mbps
SSDs stay consistent
Hard drives slow down across the platter; SSDs keep steadier speeds for long record times.
Sustained speed
Footage storage FAQ
How do I calculate video file size?
Multiply bitrate by duration, divide by 8 to convert bits to bytes, then convert to GB, GiB, or TB. This calculator applies that formula and can add a production safety margin.
How much storage does 4K video need per hour?
It depends on codec and bitrate. 4K H.265 may be around 11 GB per hour at 25 Mbps, while 4K ProRes 422 HQ at about 707 Mbps is roughly 318 GB per hour before margin.
How much space does ProRes 422 HQ use?
At common 4K 30p rates, ProRes 422 HQ is about 707 Mbps, or roughly 318 GB per hour in decimal storage units.
Does frame rate change storage needs?
Yes. For many intra-frame and camera formats, doubling frame rate roughly doubles bitrate and storage. Long-GOP H.264 or H.265 may scale less predictably because compression depends on motion and encoder settings.
Does H.265 save space compared with H.264?
Usually yes. H.265/HEVC often reaches similar visible quality at a lower bitrate than H.264, but compatibility and editing performance may be worse.
How many hours fit on 256 GB, 512 GB, or 1 TB?
Use the storage-to-record-time mode, choose a card or SSD size, and the tool estimates record time from the selected codec bitrate and safety margin.
Does audio matter for video storage estimates?
Audio is usually small compared with video. Stereo 48 kHz/24-bit PCM is about 2.3 Mbps, but multi-track audio, proxies, sidecars, and overhead can justify adding a safety margin.
Why do estimates differ from camera files?
Many codecs are variable bitrate, and cameras may use different wrappers, metadata, audio, GOP structure, or maximum bitrate limits. Treat presets as planning estimates unless your camera manual gives an exact data rate.