Drop in an mp3 and get a StepMania song folder: the tempo fitted across the whole track, the first downbeat located, and the steps written against that grid. Verify the sync against a click track before you commit to anything.
The tempo is fitted across the whole track rather than tapped from the intro, and the grid is drawn over the waveform with a click track you can play against it. A song that changes speed gets a real per-section #BPMS map instead of one average. Nudge the offset by hand if the detector was close but not right.
Stack charts the way real stepfiles do — a spread from Beginner to Challenge, or four varieties at one rating. Build them one at a time or all at once; slots are assigned so no two charts can collide, and per-difficulty rules keep a Beginner chart playable.
Point at a video ripped from the same source and its audio is cross-correlated against the song's, so #BGCHANGES starts on the beat it should. A vertical clip is fitted to a 16:9 background rather than stretched, and a song with no video of its own can have one built from its cover art, dimmed, with the music moving across it.
Open a folder that already has an .sm in it and the new chart is merged in, not written over: the banner, the preview sample and every other difficulty survive, with a timestamped backup beside them.
Paste a link from YouTube, SoundCloud or TikTok. The audio comes down with the video where there is one, so the two are aligned by construction rather than by measurement.
Step patterns come from a library of official packs, so staircases, candles and crossover entries look like something a person would write. AI mode is grounded in the same library: pick a reference song and the chart follows that era's design language.
Every song is brought to −16 LUFS so a pack does not lurch from one track to the next, and you choose whether the folder gets MP3 or OGG. The pass reports what it actually changed rather than claiming it worked.
The Framework wiki lists the patterns and the rules the generator applies — read out of the generator's own code rather than written up by hand, so what it says is what the charts actually do.
Almost nothing. Charting your own audio is free with an account — analysis, sync, every chart mode but AI. Ripping a song from a link is Pro, at $3 a month, because the download runs on our server. Only AI chart mode is metered, by the tokens it uses.