Free tools for your next audio edit
Audio file size calculator. Know the size before export.
Estimate an uncompressed PCM WAV or a fixed-bitrate audio file before exporting. Compare mono and stereo, change the recording settings, and see the maximum duration that fits within Saturalabs’ 50 MiB upload limit.
Estimated file size
11.52 MB10.99 MiB · 11,520,044 bytes
- Audio data rate
- 1,536 kbps
- Saturalabs upload limit
- 50 MiB / 52.43 MB
- Maximum duration at these settings
- 4:33.06
This estimate is within the upload limit. Check the actual exported file before uploading.
PCM calculation includes a basic 44-byte WAV header. Additional metadata or a different WAV header can increase the actual file size. Calculations run in this browser; you do not need to select a file.
For reference, the upload limit is 52.43 MB · 50.00 MiB. 1 MB = 1,000,000 bytes; 1 MiB = 1,048,576 bytes.
Plan, compare, then export
How to estimate audio file size
- 01 / FORMAT
Choose the right calculation
Select PCM WAV for uncompressed audio, or MP3 / fixed bitrate for an encoded audio payload. The WAV option does not describe every codec that can be stored inside a WAV container.
- 02 / SETTINGS
Enter duration and export settings
Choose seconds, minutes, or hours. For PCM, set sample rate, bit depth, and channels. For encoded audio, enter the total bitrate in kbps; a stereo encoder bitrate already covers both channels.
- 03 / SIZE
Check the estimate and limit
Read decimal MB and binary MiB side by side. Compare the estimate with the upload limit, then check your actual exported file. Leave headroom for tags or other metadata.
The math behind the estimate
Duration tells part of the story.
Uncompressed PCM stores a sample for every channel at each sample frame. More frames, more channels, or more bits per sample all increase the audio payload. The calculator rounds the duration to whole sample frames and includes a basic 44-byte WAV header.
PCM bytes = round(seconds × sample rate) × channels × (bit depth ÷ 8) + 44For a fixed-bitrate encoded stream, duration and bitrate determine the payload estimate. Kilobits use the decimal factor 1,000 here; dividing bits by eight converts the result to bytes. File tags, artwork, and container overhead are additional.
Encoded payload bytes ≈ seconds × bitrate in kbps × 1,000 ÷ 8For a WAV you already exported, use the WAV file inspector to read its stored settings, audio data bytes, and actual file size locally. Compare its report with this estimate rather than assuming every WAV has a 44-byte header.
The WAVE format reference from McGill explains PCM format fields, byte rates, and the chunks that make up a WAV file. Extra chunks are one reason an actual export may be larger than a basic header estimate.
Same duration, different footprints
Audio file size for one minute
PCM rows include a basic header. MP3 rows estimate encoded payload only, before metadata and framing overhead.
| Format | Settings | One minute |
|---|---|---|
| PCM WAV · mono | 44.1 kHz · 16-bit · 1 channel | 5.29 MB · 5.05 MiB |
| PCM WAV · stereo | 48 kHz · 16-bit · 2 channels | 11.52 MB · 10.99 MiB |
| PCM WAV · stereo | 48 kHz · 24-bit · 2 channels | 17.28 MB · 16.48 MiB |
| MP3 payload estimate | 128 kbps · fixed bitrate | 0.96 MB · 0.92 MiB |
| MP3 payload estimate | 320 kbps · fixed bitrate | 2.40 MB · 2.29 MiB |
Prepare an upload without guessing
How much audio fits under 50 MiB?
Saturalabs’ file limit is 52,428,800 bytes. At 48 kHz, 16-bit stereo, a basic PCM WAV can hold about 4:33.06 within that limit. Metadata may shorten the usable duration slightly. The calculator recomputes the duration for your settings.
Shortening a representative test section is often the most useful first step. It preserves your existing format while letting you inspect separation on the difficult part of the recording. The free audio trimmer cuts supported MP3 and WAV inputs and shows the exact size of its own WAV export.
A smaller file is not automatically a better source. Avoid repeated lossy re-encoding, do not increase settings to claim detail that was never recorded, and keep an untouched original. Our audio preparation guide explains which section to choose and what to keep around it.
A few useful answers
Audio file size calculator questions
How do I calculate the size of a WAV file?
For uncompressed PCM audio, multiply the number of sample frames by channels and bytes per sample, then add the file header. Sample frames are duration in seconds multiplied by sample rate. This calculator rounds to whole frames and assumes a basic 44-byte WAV header; metadata or another header layout can add more bytes.
How do I estimate MP3 file size from bitrate?
Multiply duration in seconds by bitrate in kilobits per second and by 1,000, then divide by 8 to get bytes. This estimates the audio payload at a fixed or known average bitrate. Tags, artwork, codec framing, and variable bitrate can change the final size.
Why are MB and MiB different?
A decimal megabyte (MB) is 1,000,000 bytes. A binary mebibyte (MiB) is 1,048,576 bytes. The same recording therefore has different numbers in the two units. Saturalabs accepts files up to 52,428,800 bytes: 50 MiB, or about 52.43 MB.
Does mono take half the space of stereo?
For PCM at the same duration, sample rate, and bit depth, one channel uses half the audio payload of two channels. For an MP3 encoded at a specified total bitrate, changing the channel count alone does not halve the estimated file size: the encoder’s bitrate setting determines the payload rate.
Can this calculator predict FLAC or variable-bitrate MP3 size?
Not exactly from duration alone. Their size depends on the recording and encoder. If you know the final average bitrate, the bitrate mode can provide an estimate. Otherwise, export the file and inspect its actual byte size; this tool does not assume a fixed compression percentage.
Will lowering the bitrate restore or improve audio quality?
No. A smaller estimate describes storage size, not sound quality. Re-encoding a lossy source can discard more information, and raising the sample rate or bitrate cannot recover detail already missing. Keep the best original and shorten the test section when practical.
After preparing your audio