Calculator Inputs
How to Use This Calculator
Select the calculation mode that matches your known values. Enter file size, duration, or bitrate information. Then review the detailed results above the form.
- Choose a mode and optional media preset.
- Enter values using the attached unit selectors.
- Adjust audio, video, overhead, and safety settings.
- Submit the form to calculate detailed estimates.
- Copy, print, or export the calculated results.
Main Bitrate Formulas
File size in bits ÷ duration seconds
Bitrate × duration ÷ eight
File size in bits ÷ bitrate
Total bitrate − combined audio − overhead
Sample rate × bit depth × channels
Total stream bitrate × safety factor
Example Bitrate Data
| Use case | Resolution or format | Typical video bitrate | Typical audio bitrate | Approximate hourly size |
|---|---|---|---|---|
| Voice recording | Mono audio | Not applicable | 64 kbps | 29 MB |
| Podcast | Stereo audio | Not applicable | 128 kbps | 58 MB |
| SD video | 854 × 480 | 1.5 Mbps | 128 kbps | 733 MB |
| HD video | 1280 × 720 | 3 Mbps | 160 kbps | 1.42 GB |
| Full HD video | 1920 × 1080 | 6 Mbps | 192 kbps | 2.79 GB |
| 4K video | 3840 × 2160 | 25 Mbps | 320 kbps | 11.39 GB |
Actual requirements vary by codec, motion, quality, and platform limits.
Understanding Bitrate
Bits and Bytes
Bitrate normally uses bits per second. File sizes usually use bytes. Eight bits always equal one byte.
Constant and Variable Bitrate
Constant bitrate holds a steady data rate. Variable bitrate changes with media complexity. Average values provide practical storage estimates.
Codec Efficiency
Modern codecs often preserve quality at lower bitrates. Encoding settings still affect visible results. Test representative footage before final delivery.
Streaming Headroom
Upload capacity should exceed the stream bitrate. Extra headroom reduces connection instability. Wired connections often provide steadier live delivery.
Frequently Asked Questions
What does bitrate measure?
Bitrate measures data transferred or processed each second.
Are Mbps and MBps identical?
No. MBps measures bytes and equals eight Mbps.
How does bitrate affect file size?
Higher bitrate creates larger files at equal durations.
Does higher bitrate always improve quality?
No. Codec limits and source quality also matter.
What is container overhead?
It covers metadata, indexing, headers, and stream packaging.
Why add upload safety margin?
Headroom protects streams during normal connection speed changes.
Can this estimate surveillance storage?
Yes. Enter each camera stream and retention duration.
How accurate are variable bitrate estimates?
Accuracy depends on the real average encoding bitrate.
What bitrate should podcasts use?
Speech often uses lower rates than complex music.
Can several audio tracks be included?
Yes. The calculator combines every configured audio track.
Are calculated values guaranteed?
No. Final files vary with encoders and containers.