Audio file size calculator

( 01 )

Formula and units

Compressed bytes = duration in seconds × bitrate in kbps × 1,000 ÷ 8. The calculator uses decimal kbit/s, shows storage in decimal MB/GB, and also shows binary MiB/GiB so the same byte count is not mistaken for two different files.

( 02 )

What the estimate includes

• It models constant bitrate (CBR) or a known average bitrate. Variable-bitrate files can differ because their actual average rate depends on the encoded audio.
• Container headers, tags, artwork, encoder padding, and other metadata are excluded, so an exported file may be slightly larger.
• Bitrate describes data per second; it does not prove perceptual quality. Codec, source, and encoder settings also matter.
• For lossless formats such as FLAC, size cannot be predicted exactly from duration alone because compression depends on the signal.

( 03 )

Useful for storage and export planning

• Estimate podcast episode storage before recording or publishing.
• Compare MP3 bitrate choices before using the converter.
• Plan a music, audiobook, lecture, or voice-note archive.
• Check whether a batch is likely to fit a storage or upload allowance.

( 04 )

The calculation stays in this tab

This page does not request an audio file. The values you type are multiplied locally in your browser; no media is uploaded for this estimate. The site may still load normal page resources and consented analytics.