Cascade

Convert osu!mania maps to StepMania / Etterna online

Cascade converts osu!mania beatmaps (.osz / .osu) into StepMania and Etterna-compatible .sm charts directly in your browser. There is nothing to install and nothing to upload to a server: the conversion runs locally on your machine.

How to convert .osz to .sm

1. Open Cascade and drag your .osz (or a single .osu with its audio) onto the page.
2. Check the chart: notes, holds, BPM changes and offsets are all editable before export.
3. Choose File → Export .sm. Cascade writes a StepMania package with the audio and background bundled.

What carries over

• Notes and long notes (holds), for 4K up to 10K+ keymodes
• BPM changes and the timing offset
• Song metadata: title, artist, creator, plus StepMania-specific fields like #SUBTITLE, #GENRE and #DISPLAYBPM which you can edit in Map Settings
• Audio (WAV is re-encoded automatically) and the background image

Converting in the other direction

Cascade also imports .sm files and whole StepMania / Etterna packs, so you can bring an Etterna chart in, edit it on an osu!-style playfield, and export it as .osu or .osz for osu!mania.

Why not a script?

Offline converter scripts exist, but they give you no way to check the result. Cascade shows the converted chart on a scrolling playfield with audio, so you can play it back, fix timing or patterns, and only then export. It doubles as a full online osu!mania editor and an osu!mania map viewer.