Audio File Size Calculator
Estimate an audio file's size at any bitrate, and see how many tracks fit on a CD or in a gigabyte.
Convert with this tool
Files stay on your device. There is no upload, no queue and no watermark, so a conversion works even with the network switched off after the page has loaded.
Supported formats & processing
| Input | Numbers you type — nothing is calculated until you change a value |
|---|---|
| Output | A live result table, recalculated on every keystroke |
| Processing | Plain arithmetic in this tab — instantaneous and offline |
About this tool
Audio file sizes are predictable in a way that video sizes are not, because a constant-bitrate audio encode really does use the same number of bits every second. That makes planning straightforward: a 320 kbps MP3 is about 2.4 MB per minute, and a CD-quality WAV is about 10 MB per minute.
This calculator reports the size for a chosen bitrate and duration, then puts it in context by showing how many tracks of that length fit on a 700 MB CD or in a gigabyte. It is the quickest way to decide between delivering at 128 kbps and 320 kbps when storage is the constraint.
Features
- Seven bitrate options from 64 kbps to CD-quality PCM
- Duration entered as minutes and seconds
- Size per minute for quick mental arithmetic
- Track count for a 700 MB CD and for one gigabyte
- Accurate for constant-bitrate encodes
- Useful for planning podcast archives and audiobook libraries
Frequently asked questions
How large is a typical song?
A four-minute track is about 3.8 MB at 128 kbps, 5.8 MB at 192 kbps and 9.6 MB at 320 kbps. As uncompressed CD audio it is about 42 MB.
Why is my audiobook larger than the estimate?
Variable-bitrate encoding and chapter metadata both add bytes, and many audiobook files carry cover art. A few hundred kilobytes of artwork on a short file can be a noticeable proportion of the total.
What bitrate should I use for a podcast?
96 kbps mono or 128 kbps stereo is transparent for speech and keeps an hour-long episode around 45–58 MB, which is comfortable for podcast hosts and mobile downloads.
Is 1411 kbps really CD quality?
Yes. CD audio is 44.1 kHz, 16-bit stereo, which is 44,100 × 16 × 2 = 1,411,200 bits per second. That is the uncompressed PCM rate.