What is the Video File Size Calculator?
Estimate encoded video data size by combining video and audio bitrates over time.
The result is a bitrate-based estimate and does not predict a specific codec quality level.
How to use the Video File Size Calculator
Start with measurements from the same device, connection, file, or scenario whenever possible. Enter Duration minutes, Duration seconds, Video bitrate, Audio bitrate using the units printed beside each field. Avoid mixing bits with bytes, decimal storage units with binary units, or peak specifications with typical operating values.
- Collect the requested values and confirm their units before entering them.
- Choose realistic efficiency, overhead, compression, reserve, or usage assumptions where those options are provided.
- Select Calculate Video Size, then review the primary answer, all four color-coded detail cards, the caution note, and the five calculation steps.
For planning decisions, repeat the calculation with a lower, expected, and higher assumption. A range usually communicates uncertainty better than one apparently precise number.
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For optional supporting equipment or reference material, you can browse Data storage devices (paid link) on Amazon.com. Compare usable capacity, device compatibility and backup needs with your estimate. Nominal capacity differs from usable space; a file-size estimate does not replace a backup strategy. No purchase is required to use this calculator.
How to understand the result
The result is a bitrate-based estimate and does not predict a specific codec quality level.
The large highlighted value is the main estimate. The cyan, purple, green, and orange cards provide supporting quantities such as converted units, intermediate totals, rates, physical dimensions, capacity, or time. These details make it easier to check whether the result is reasonable.
Display and media estimates separate pixel dimensions from physical dimensions and encoded file size. Nominal screen measurements, rounded corners, scaling, chroma subsampling, variable bitrate, metadata, containers, and codec settings can all create differences between a calculated value and a product specification or exported file.
Example and practical interpretation
For example, 120 minutes 30 seconds at 8 Mbps video plus 192 Kbps audio is about 7.404 GB. Use an expected average bitrate for variable-bitrate encodes and allow extra space for container data or additional tracks.
The five-step explanation beneath the result uses the exact values entered during the current calculation. It shows the conversion or setup, the formula, intermediate arithmetic, final operation, and displayed rounding rather than presenting a generic formula alone.
Formula and calculation method
The calculation runs locally in your browser and uses only the values entered on this page.
Important limitations
Technology estimates simplify real systems. Hardware, software, network conditions, measurement conventions and manufacturer behavior can change actual results.
Video File Size Calculator FAQs
Sources and methodology
Official source links support terminology and measurement context. The arithmetic runs locally in your browser.