Technology

Video Bitrate Calculator

Solve for video file size, bitrate, or duration from the other two values. Handles Mbps, kbps, MB and GB with this free video bitrate calculator.

Video Bitrate Calculator

Solve for

File size

Size unit

Bitrate

Bitrate unit

Duration

minutes

seconds

Method

How this calculator works

The core relationship is fileSize_bits = bitrate_bps × duration_seconds, and fileSize_bytes = fileSize_bits ÷ 8. Rearrange to solve for whichever value is unknown: bitrate = bits ÷ seconds, or duration = bits ÷ bitrate.

Choose what you want to solve for: File Size, Bitrate, or Duration.
Enter the two known values in the fields that appear.
The tool applies fileSize_bits = bitrate × duration, converting units as needed.
Read the solved value as the primary result, with a secondary unit shown for reference.

Examples

Worked examples

Real numbers, end-to-end results.

10 Mbps × 60 sec

= 75 MB

10,000,000 bits/s × 60 s = 600,000,000 bits ÷ 8 = 75,000,000 bytes.

1.5 GB over 30 min

= 6.67 Mbps

1.5e9 × 8 = 1.2e10 bits ÷ 1,800 s = 6,666,667 bits/s.

700 MB at 4 Mbps

= 0:23:20

700e6 × 8 = 5.6e9 bits ÷ 4,000,000 bits/s = 1,400 s.

Use cases

When to use it

Pick an export bitrate that fits a target upload or storage size.
Estimate how long a clip can run before it exceeds a size limit.
Reverse-engineer the average bitrate of an existing video file.
Plan streaming quality against bandwidth and data caps.

FAQ

Frequently asked questions

What is video bitrate?

Bitrate is the amount of data used per second of video, usually measured in megabits per second (Mbps) or kilobits per second (kbps). Higher bitrate means better quality and a larger file for the same length.

How do I calculate video file size from bitrate?

Multiply the bitrate in bits per second by the duration in seconds to get total bits, then divide by 8 to get bytes. For example, 10 Mbps for 60 seconds is 600,000,000 bits, or 75 MB.

How do I find the bitrate for a target file size?

Convert the target size to bits (bytes × 8) and divide by the duration in seconds. This gives the average bitrate in bits per second, which you can convert to Mbps by dividing by one million.

What bitrate should I use for 1080p video?

For 1080p at 30fps, YouTube recommends around 8 Mbps, while high-quality uploads may use 12–16 Mbps. The right value depends on motion, codec, and platform, so use this tool to preview the resulting file size.

Does this calculator use decimal or binary megabytes?

It uses decimal units, where 1 MB is 1,000,000 bytes and 1 GB is 1,000,000,000 bytes, which matches how bitrate and streaming sizes are normally quoted.