Stop choosing the louder file.You know the moment. Two versions of the same mix, and you keep picking the second one — because it's 0.8 dB louder, not because it's better. Your ears can hear the difference. Your brain doesn't stand a chance against level.Blind A/B takes away everything except the sound.Load two mixes. The filenames disappear. A and B get shuffled. Both files are matched to the same measured loudness — real BS.1770 K-weighted gated LUFS, matched attenuate-only, so the quieter file is never boosted to fake a win. Then it cross-correlates the two files and sample-locks them, so you're always comparing the same moment of the song.Then you just listen.Hit SPACE to catch whatever is playing, and drop it on a section. Verse, chorus, bridge — lock in your pick section by section. MY EDIT shows the whole song tinted by your decisions, and plays back the comp you just built out of your blind picks.Then hit REVEAL, and find out which mix actually won.What's in it Blind by default — filenames hidden, A/B sides shuffled every load True BS.1770 loudness matching, attenuate-only Two-stage cross-correlation auto-alignment, sample-locked Section-by-section comping — catch & drag Export your comp to WAV — 32-bit float, 24-bit or 16-bit, at the source's native sample rate True-peak warnings for inter-sample clipping How it runsOne file. Double-click it. It opens in your browser and runs entirely offline, on macOS, Windows or Linux. No installer, no account, no sign-in, no dependencies, nothing to keep updated. A native Mac app is included in the download if you'd rather have it in your dock.Your audio never leaves your machine.Not one network request at runtime. Load a record that isn't out yet — nothing is uploaded, nothing is logged, nothing phones home. You can verify it: pull your Wi-Fi and it works exactly the same.Built by a working producer who got tired of picking the louder file.