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Audio Inspector

See everything about an audio file: duration, format, codec, sample rate, bit depth, channels and bitrate, the embedded tags and cover art, plus measured peak and RMS levels and a waveform overview.

Everything runs locally in your browser. Your data never leaves your device.

Drop audio files here

or click to browse (MP3, FLAC, WAV, Ogg, Opus, M4A, AAC and more)

Drop several files at once to inspect them one after another.

About the Audio Inspector Tool

This tool reads everything an audio file will tell about itself. Drop in an MP3, FLAC, WAV, Ogg, Opus or M4A and it lists the container, codec, duration, sample rate, bit depth, channel layout and bitrate, with a plain verdict on the encoding quality.

It also shows the embedded tags, from title and artist to track numbers and the cover art, which you can save as an image. Below that, the file is decoded and actually measured: peak level and RMS loudness in dBFS, a clipped-sample count and a waveform overview of the whole recording, with a player to listen along.

What you can do

  • Check the bitrate and sample rate of an MP3 or any other audio file.
  • See whether a file is lossless or lossy, and whether an MP3 is CBR or VBR.
  • View the ID3 tags and other metadata embedded in an audio file.
  • Extract the cover art from an MP3 or FLAC and download it as an image.
  • Measure the peak level and RMS loudness of a track in dBFS.
  • Detect clipping by counting samples at full scale.
  • See the waveform of an audio file and play it back.

How to use the Audio Inspector

  1. 1Drop in an audio file, or several at once to inspect them one after another.
  2. 2Read the format panel for duration, codec, sample rate, bit depth, channels and bitrate.
  3. 3Check the tags panel for the title, artist, album and cover art, with a download button for the art.
  4. 4Scroll to the levels panel for the measured peak, RMS loudness, clipping count and the waveform.
  5. 5Use the built-in player to listen while you read the numbers.

Measured levels, not tag values

Peak and RMS come from decoding the file and measuring every sample, not from ReplayGain or loudness tags, so they reflect the audio as it actually decodes. Peak is the loudest single sample and RMS is the average energy over the whole file, both in dBFS where 0 is full scale. Samples at or within a hair of full scale are counted as clipped, per channel and in total.

What the quality line means

Lossless files are judged by resolution: 16-bit at 44.1 kHz is CD quality and anything beyond counts as hi-res. Lossy files are tiered by bitrate, since that is the best single predictor of how they sound. The verdict is a rule of thumb, not a listening test.

Long recordings

Measuring levels expands the whole file to raw samples in memory. For very long recordings the tool estimates that cost first and asks before decoding, so a multi-hour recording never freezes the page by surprise. The format details and tags always load right away. For video files, the Video Inspector does the same job for MP4, WebM and MKV.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • music-metadata

    A metadata parser that understands the tags of virtually every audio format.

Everything this site builds on is listed on the credits page.

Convert audio files between MP3, WAV, OGG, FLAC and M4A. Drop in as many files as you like, pick the target format and bitrate, and download the results one by one or all at once.

View and edit the ID3 tags of an MP3, including title, artist, album, year, genre, track number, lyrics and cover art. Reads the existing metadata of other audio formats too, and saves a tagged copy of your MP3.

Cut a section out of an audio file on a zoomable waveform timeline. Drag the start and end handles, play back just your selection, fade the edges if you like, and export the result as MP3, WAV, OGG, FLAC or M4A.

Create barcodes in dozens of formats, from EAN-13, UPC-A and Code 128 to QR Code, Data Matrix and PDF417. Type the content, tune the size, colors and text options, and download the result as PNG or SVG.

See any image the way people with a color vision deficiency see it. Upload a picture and preview protanopia, deuteranopia, tritanopia, the milder anomalous forms and monochromacy next to the original, then download any simulation as a full resolution PNG.

Pull the dominant colors out of any image as a ready-to-copy palette. Choose how many colors you want, copy each one as HEX, RGB or HSL, and export the whole palette at once.