Question 1

How do I check the codec of an audio file?

Accepted Answer

Select or drag an audio file into the checker. The detected codec appears at the top of the results, with the file's format, bitrate, sample rate, channel count, duration, and size shown below it.

Question 2

What is an audio codec?

Accepted Answer

A codec is the method used to encode and decode the audio data. Common examples include MP3, AAC, Opus, Vorbis, FLAC, and PCM. The codec determines which apps and devices can play the file and whether the audio is compressed losslessly or with some data removed.

Question 3

What is the difference between a codec and a file format?

Accepted Answer

The codec describes how the audio is encoded, while the file format or container describes how that audio is packaged. For example, an M4A file commonly contains AAC audio, and an OGG file may contain Opus or Vorbis audio. The file extension alone does not always identify the codec.

Question 4

Why does the detected codec not match the file extension?

Accepted Answer

A file extension may identify its container rather than its codec, or the file may have been renamed without being converted. The checker reads the audio data inside the file, so its result can differ from the name at the end of the filename.

Question 5

Why does the codec matter when an audio file will not play?

Accepted Answer

A device or app must support both the file's container and its codec. If playback fails, compare the detected codec with the formats supported by the player, browser, car stereo, editing app, or platform you are using.

Question 6

Can I make an unsupported file work by changing its extension?

Accepted Answer

No. Renaming the file does not change how its audio is encoded. You need to convert the file to a codec and container supported by the destination device or app.

Question 7

Does the codec tell me whether the audio is lossless?

Accepted Answer

It identifies the encoding type. FLAC is lossless, PCM is uncompressed, and MP3, AAC, Opus, and Vorbis are lossy. However, a lossless codec does not prove that the file came from a lossless source; previously compressed audio can be saved as FLAC without restoring removed detail.

Question 8

Can I judge audio quality from the codec alone?

Accepted Answer

No. Quality also depends on the bitrate, encoder settings, and source recording. The codec result is useful for compatibility and for identifying the encoding family, but it is not a complete measure of sound quality.

Question 9

What does “Unknown” mean?

Accepted Answer

The file may use a codec the checker cannot identify, may be damaged or incomplete, or may not contain valid audio data. Confirm that the file opens elsewhere and try obtaining or exporting a fresh copy.

Question 10

Can I use this checker for the audio track in a video file?

Accepted Answer

This checker is intended for audio files. For MP4, MOV, WebM, MKV, or another video container, use the video file info tool to inspect its video and audio tracks.

Audio codec checker

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