Video File Size Calculator
Estimate how much storage your video will use from bitrate and duration.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Video File Size Calculator
- Select a preset (optional). The preset list includes common delivery formats like YouTube 4K (35 Mbps), 1080p 30fps (8 Mbps), Instagram Reels (3.5 Mbps), and Netflix 4K HDR (15.6 Mbps). Selecting a preset fills in the bitrate field automatically.
- Enter the duration in minutes. For a 30-second clip, type 0.5.
- Set the bitrate in Megabits per second. If you know the bitrate your camera or encoder uses, type it here. Check your camera's video settings or the output settings of your editing software.
- Read the result. The calculator shows file size in both MB and GB, updating instantly as you type.
This estimate is for the video stream only, calculated as: size (MB) = bitrate (Mbps) × duration (sec) / 8. Container overhead, audio tracks, and metadata add a small amount on top, but this gives a reliable planning estimate.
About Video File Sizes
Video file size is determined almost entirely by bitrate and duration. Bitrate is the amount of data per second, measured in Megabits per second (Mbps). A 4K video at 35 Mbps produces a much larger file than a 1080p video at 8 Mbps, even at the same duration. Higher bitrates preserve more detail and color accuracy but require more storage and faster storage devices for smooth playback.
Typical bitrates by format: smartphone video records at 25-100 Mbps depending on the codec. YouTube recommends 35-45 Mbps for 4K uploads. Instagram caps uploads at lower bitrates and recompresses everything. Broadcast-quality ProRes files can exceed 100 Mbps. H.265 (HEVC) encoding achieves similar quality to H.264 at roughly half the bitrate.
Frequently Asked Questions
How large is an hour of 4K video?
At a common 4K bitrate of 25 Mbps, one hour of 4K video is approximately 11.25 GB. At the YouTube recommended 35 Mbps, that rises to about 15.75 GB per hour. Camera-recorded 4K with higher bitrate codecs like ProRes can reach 100 GB or more per hour.
What is the file size of a 1-minute 1080p video?
At 8 Mbps (a common 1080p 30fps bitrate), one minute of video is 60 MB. At 12 Mbps (1080p 60fps), it is 90 MB. Streaming platforms often target even lower bitrates after recompression, typically 3-6 Mbps for 1080p delivery.
Why does my exported video file differ from the estimate?
Most modern codecs use variable bitrate (VBR) encoding, which uses more data for complex scenes and less for simple ones. The calculator assumes constant bitrate (CBR). Audio tracks, subtitles, and container metadata also add file size on top of the video stream. For accurate storage planning, add 5-10% over the calculated estimate.
What bitrate should I use for YouTube uploads?
YouTube recommends 35-45 Mbps for 4K HDR, 15-20 Mbps for 4K SDR, 10-20 Mbps for 1080p 60fps, and 8 Mbps for 1080p 30fps. Uploading at a higher bitrate than recommended does not improve quality after YouTube reprocesses the file, but it gives the encoder more data to work with and typically results in slightly better compressed output.