Audio File Size
Estimate a compressed audio file size from bitrate and duration.
About Audio File Size
Multiplying the bitrate by the length in seconds and dividing by eight yields the stored bytes of the file. Bitrate is the main knob on quality and size for lossy formats, so estimating size tells you how much library fits on a drive.
Formula
Audio File Size
File size = bitrate x duration / 8
- bitrate
- Kilobits consumed per second of audio
Worked example
With the default values below, Audio File Size returns File Size of 7 MiB. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Bitrateminimum 8 kbps
- 320 kbps
- Durationminimum 0.1 s
- 180 s
Results
- File Size
- 7 MiB
- File Size
- 6.87 MB
- Per Hour
- 137.33 MB
Step by step
- 1Values used
- 2Audio File Size
- 3File Size= 7,200,000
- 4File Size= 6.87 MB
- 5Per Hour= 137.33 MB
Assumptions and limits
- The result is derived only from the 2 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, tax, fees or charges or compounding frequency into account.
- Figures are rounded for display to 2 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Audio File Size calculated?
File size = bitrate x duration / 8 Multiplying the bitrate by the length in seconds and dividing by eight yields the stored bytes of the file.
Why does Audio File Size matter?
Bitrate is the main knob on quality and size for lossy formats, so estimating size tells you how much library fits on a drive.
What values do I need to enter?
This calculator takes 2 inputs: Bitrate, Duration. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.