Most online cutters decode your MP3 and encode it again, so the part you keep goes through a second round of lossy compression. This one does not: an MP3 is a run of self-contained frames, so a cut on a frame boundary is a byte copy, and the kept audio comes out unchanged. Cuts snap to the nearest frame — about 26 ms — and the tool tells you how far the snap moved your request. Choose Precise when you need the exact sample or a fade; that path decodes and exports WAV.