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How to save BPM values inside ID3 tags
In the latest ID3v2 specification there are 84 types of frame, and applications can also define their own types. There are standard frames for containing BPM values. BPM Counter can add or update standard BPM frame. With that done, it's a simple matter of sorting your music library by the beats-per-minute field.
The BPM is an integer and represented as a numerical string according ID3 standard. Many customers required better accuracy, so we decided to use a floating point values. Most audio software will ignore decimal values, but if you have compatibility issues you can set the number of decimal digits to zero in BPM Counter options.