Video File Size Calculator
Estimate a video file's size from its bitrate and length.
Video file size depends on its bitrate and how long it runs.
How the Math Works
The Video File Size Calculator uses the formula size = bitrate × duration × 60 / 8, where bitrate is in megabits per second (Mbps), duration is in minutes, and size is calculated in megabytes (MB). The multiplication by 60 converts minutes to seconds, ensuring the time unit matches the bitrate's per-second rate. Dividing by 8 converts bits to bytes (since 1 byte = 8 bits), and since the bitrate is in megabits, the final result is in megabytes. This formula simplifies complex unit conversions into an intuitive calculation for quick estimations.
Practical Applications
To use this calculator, input the video's bitrate (e.g., 5 Mbps for HD quality) and its duration (e.g., 30 minutes). The result helps determine storage needs for editing, sharing, or archiving. For example, a 5 Mbps video lasting 10 minutes would require approximately 37.5 MB of space. Content creators can adjust bitrate settings to meet platform requirements, while IT professionals might estimate network bandwidth for video transfers or streaming servers.
Day-to-Day Use
This tool simplifies everyday tech decisions: checking if your device has enough storage for a movie, estimating download times based on internet speed, or planning backups. It also helps choose optimal video quality—balancing file size with visual fidelity. For instance, reducing bitrate can save space for limited storage devices, while knowing file sizes aids in organizing cloud storage or external drives efficiently.
Worked example
10 Mbps for 30 minutes is about 2.25 GB.
FAQ
How do I shrink it?
Lower the bitrate or resolution, or use a more efficient codec like H.265.