Audio File Size Calculator

Estimate constant-bitrate audio file size from total audio bitrate and duration.

Audio bitrateNumber from 0.001 to 1000000 kbit/s.HoursWhole number from 0 to 100000.MinutesWhole number from 0 to 59.SecondsNumber from 0 to 59.999.

Use consistent units exactly as labeled. Decimal and scientific notation are accepted for non-integer fields; blanks, commas, fractions and non-finite entries are rejected.

Calculate

Duration3600 sec

Estimated file size144 MB

Estimated file size137.3291016 MiB

Data per minute2.4 MB

The displayed results apply to the default example. Enable JavaScript to calculate other inputs.

How to use this calculator

1. Replace the example values with your own measurements, schedule, prices, or media settings.
2. Keep each value in the unit printed beside its field.
3. Select Calculate and review every result together with the assumptions below.

Formula and method

Bytes = kbit/s × 1,000 × seconds ÷ 8. MB uses 10⁶ bytes; MiB uses 2²⁰ bytes.

Calculations run in your browser. Results are hidden whenever an input changes or validation fails, preventing an old answer from being mistaken for the current calculation.

Worked example

Audio bitrate = 320 kbit/s; Hours = 1; Minutes = 0; Seconds = 0. The calculator returns Duration = 3600 sec; Estimated file size = 144 MB; Estimated file size = 137.3291016 MiB; Data per minute = 2.4 MB.

The worked example uses the same default values shown in the interface, so the displayed result and explanation can be checked directly.

Limitations

Variable bitrate, tags, cover art, container overhead and multiple tracks can change actual size. Uncompressed audio should be calculated from sample rate, bit depth and channels instead.

Use the result as a planning estimate. Confirm prices, policies, equipment ratings, units and professional requirements that apply to your situation.

Frequently asked questions

Is 320 kbit/s the same as 320 kB/s?

No. Eight bits make one byte, so 320 kbit/s equals 40 kB/s before overhead.

Why does the calculator reject my entry?

Each field shows its supported range. Whole-number fields reject decimals, and all fields reject blanks, words, comma-formatted numbers, fractions and non-finite values.

How should I round the result?

Keep extra digits while planning, then round to the precision supported by your inputs, package sizes, billing rules or equipment settings.

Review notes and reference

Reviewed October 4, 2026. The formula was checked against the displayed worked example. The script was tested for defaults, field boundaries, invalid formats, condition-specific errors and recovery after an error. Reference: NIST guidance on bits, bytes, and binary prefixes. Explanations and examples are original.

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