4K isn’t a file size.
Two cameras shooting 4K can make very different files. Bitrate is the amount of data recorded each second. Use the bitrate in your camera settings, or estimate it from a sample clip.
Mbps = file size in MB × 8 ÷ seconds
THE VIDEO STORAGE CALCULATOR
Video storage
calculator.
Make room for the whole story.
Estimate video file size, SD cards and recording time for your next shoot.
YOUR MEMORY PLANESTIMATE
425.3GB
for the whole shoot, including 20% breathing room.
2 × 256 GBEnough for all 7 days.
83% of available card space
Footage5h 15m
Per card, with margin3h 9m
Backup drive, per copy512 GB
Keep a separate copy of your footage.
A spare card is not a backup.
Finish the highlighted fields to see your memory plan.
Free to use. No sign-up. Calculated in your browser.GB = 1,000,000,000 bytes
02 / THE QUICK REFERENCE
How long
can you roll?
Recording time by card size, using your selected bitrate and safety margin.
| Card size | Recording time | Cards to pack |
|---|---|---|
| 64 GB | 47m | 7 |
| 128 GB | 1h 34m | 4 |
| 256 GB | 3h 9m | 2 |
| 512 GB | 6h 19m | 1 |
| 1 TB | 12h 20m | 1 |
Capacity is not write speed. Check your camera’s supported card sizes and speed classes before buying.
03 / FIELD NOTES
A little knowledge.
A lot more peace of mind.
The math, in the open.
We multiply bitrate by recording time, convert bits to bytes, then add your chosen margin. At 100 Mbps, an hour of footage is approximately 45 GB before the margin.
GB = Mbps × seconds ÷ 8,000
Make a copy. Then another.
Clearing cards reduces how many you need to carry, but all that footage still needs a home. Each recommended backup drive holds a complete copy. Choose one, two or three independent copies in Advanced. Verify separate copies before erasing your cards.
Two copies. Two separate places.
A QUICK START
How much space
does 4K video need?
The same resolution can produce very different file sizes. These examples show what changes when the bitrate changes.
| Recording bitrate | Storage per hour |
|---|---|
| 60 Mbps | 27 GB |
| 100 Mbps | 45 GB |
| 120 Mbps | 54 GB |
| 200 Mbps | 90 GB |
Illustrative bitrates, not specifications for a particular camera. 4K, Full HD, frame rate and codec alone do not determine file size.
How long can a 128 GB or 256 GB SD card record?
At 100 Mbps, an empty 128 GB card holds about 2 hours 50 minutes; a 256 GB card holds about 5 hours 41 minutes, before formatting and other files. With 20% extra capacity reserved, plan for about 2 hours 22 minutes and 4 hours 44 minutes respectively.
Choose Advanced → Check a card above to calculate recording time at your own bitrate. To plan a trip without knowing technical settings, start with Simple.
Before you pack.
Will this work with my GoPro, DJI, phone or mirrorless camera?
Yes. Start in Simple: choose GoPro, DJI, Insta360, a drone, phone or another camera. If recording settings are unfamiliar, choose “I’m not sure.” Brand choices are broad planning profiles, not exact camera specifications. Use the 360° option for GoPro MAX and Insta360 X-series footage; use Action camera for Insta360 Ace or GO single-lens recording. For more precision, use Advanced and enter the bitrate from your camera settings or a sample clip. Profiles are illustrative, not specifications for any camera. Frame rate, codec and scene complexity can change the space you need.
Why does my card show less space on my computer?
Card makers use decimal GB. Some systems display binary GiB: 256 GB is about 238.4 GiB before formatting. This calculator consistently uses decimal GB. Formatting, photos and other files also consume space; allow a margin and use empty cards.
Does this include photos, proxies and slow motion?
By default the estimate includes the video stream represented by your bitrate. In Advanced, add a percentage for photos, audio, proxies and other files. Already-used space is subtracted from every card. Multiple cameras use the same recording settings and each gets its own whole number of cards. For slow motion, use the recording bitrate and real recording duration, not the slowed-down playback duration.
How accurate are the results?
The arithmetic is exact for a constant bitrate. Real footage often uses variable bitrate. A maximum bitrate gives a conservative estimate; a sample clip gives an estimate for similar scenes. The default 20% margin is adjustable and cannot guarantee that your footage will fit.
What happens to my data?
Calculations run in your browser and do not require an account. If you allow analytics, Google Analytics uses cookies to measure visits, referring websites, device/browser information, engagement time, scroll depth and calculator actions. We do not send your saved plan link or individual calculator values. Advertising features are disabled. You can decline analytics and still use every feature, or change your choice below. Your choice is saved on this device for six months. The hosting provider keeps ordinary access logs. Copying a plan stores settings in its URL fragment, which is not sent to our web server.