Audio File Inspector
See the duration, sample rate, channels, container and measured levels of an audio file.
Fill in the form and press “Inspect” to see the result here.
How to use it
- 1Choose a file, or drag it onto the upload area.
- 2Press the button. Your browser decodes the file locally.
- 3Read the results. Nothing was uploaded, so there is nothing to clean up.
About the Audio File Inspector
Reports what the file actually contains rather than what its name claims: the container is identified from its first bytes, and the duration, sample rate and channel count come from decoding it.
Peak and RMS levels are measured across the whole recording. Peak is the single loudest sample; RMS is much closer to how loud it sounds. A file with a peak at 0 dBFS and an RMS around -20 dBFS is normal for music.
What a browser cannot tell you is the encoder and its settings - that information is not exposed to web pages by any API.
Questions people ask
Is my file uploaded?
No. The file is decoded by your own browser and the result is displayed locally. Nothing leaves your device, there is nothing on a server to delete, and this works with no network connection at all.
Why does a large file fail?
Decoding holds the audio in memory uncompressed - roughly 10 MB for every minute of stereo. Long recordings run out of memory in a browser tab, which is why there is a size limit. The queued FFmpeg tools handle bigger files.
Is it free, and do I need an account?
Yes, it is free, and there is no account, no sign-up and no watermark on the result. The project is funded by optional donations.