Audio File Size
Estimate audio file size from duration and format
How to use Audio File Size
- 1Enter the audio length and sampling rate (e.g. 44.1 kHz).
- 2Select a bit depth or code rate (no damage or impairment).
- 3Reads the estimated file size under the corresponding format.
Resize Audio Files
Size = sample rate x bit depth x number of acoustic channels x length (PCM); or code rate x length (compression)The size of uncompressed audio increases with sampling rates, bit depths and acoustics; stereos are twice as large as a monosound.
MP3/AAC, for example, is stored in target-code rates, while FLAC does not compress PCM data without loss and does not discard information.
Audio volume formulae (detrimental format): ** Size (MB) = code rate (kbps) x length (sec) ÷ 8 ÷ 1024**. Example: 4-minute songs from 320 kbps = 320 x 240 ÷ 8 ÷ 1024 ≈ 9.4 MB. WAV is calculated in a different manner, depending on the sampling rate, bit depth, acoustic number:** bytes per second = sampling rate x bit depth ÷ 8 x acoustics**. CD sound (44.1 kHz, 16 bit, stereo) = 44100 x 2 x 2 = 176,400 bytes/sec, approximately 10.1 MB/min.
** Non-destructive formats do not all account for large space**: FLAC, ALAC, APE are all compressed and intact (like ZIP), so FLAC is about 300-400 MB an hour, and WAV is about 635 MB. Selection proposal: The parent tape archive is WAV/AIFF, the music collection is FLAC, and mobile devices are 256-320 kbps AAC/MP3. ** Note that MP3 is a proprietary format (now expired), AAC is slightly more efficient than MP3 (better sound at the same code) and Opus is the best performer (suitable for voice and real-time communication) at a low-code rate. **
| Format / Code Rate | 1 minute | 1 hour | No damage? |
|---|---|---|---|
| MP3 128 kbps | 0.96 MB | 57.6 MB | Yes |
| MP3 192 kbps | 1.44 MB | 86.4 MB | Yes |
| MP3 320 kbps | 2.40 MB | 144 MB | Yes |
| AAC 256 kbps | 1.92 MB | 115 MB | Yes |
| OGG 192 kbps | 1.44 MB | 86 MB | Yes |
| FLAC (no damage, approximately 900 kbps) | 6.75 MB | 405 MB | Yes. |
| WAV 44.1k/16bit stereo | 10.6 MB | 635 MB | Yes. |
| WAV 48k/24bit stereo | 17.3 MB | 1.04 GB | Yes. |
1 hour file volume in common audio format
Frequently asked questions
WAV with FLAC who's big?
WAV is the original PCM (maximum); FLAC undamaged compression is usually 50-60% small.
Better than that?
When only sound sources and ears can be used; 44.1/48 kHz is enough for most listeners.
Why is the stereo twice as mono?
Two channels each store independent samples, and the data rate doubles.
Why is the same rate AAC better than MP3?
AAC is a successor to MP3 and has improved several techniques: more flexible block length, better stereocoding, more efficient entropy, and better transient processing. The AAC sound quality is clearly better than MP3 at the measured homogeneity rate, especially under 128 kbps, which is why the iTunes/YouTube uses AAC. The low-rate (< 96 kbps) scene gap is even more exaggerated, at which point Opus is clearly better than AAC. In pursuing volume efficiency, the priority is: Opus > AAC > MP3.
Will conversion lose the sound quality?
** The conversion between impaired formats will inevitably accumulate losses** (MP3 → AAC → MP3 with each recoding drop of information once more and three generations later with obvious underperformance). The correct course of action is to keep a non-damaged mother belt (FLAC/WAV) at all times and to transfer it once in whatever format it requires. ** No loss, no loss, no loss** (WAV → FLAC → WAV received the same bytes of the original document). So it's pointless to "turn the music to MP3 and return to nothing" — lost information won't come back.