BGM Box
Your Nintendo BGM Toolkit
Convert, Play, Loop — All in one box.
Free online tools for Nintendo audio formats (BRSTM, BCSTM, BFSTM). No sign-up, no installation, everything runs in your browser.
Three Tools in One Box
Convert
MP3, WAV, OGG → BRSTM, BCSTM, BFSTM. Multi-channel (up to 8ch), visual loop point editor, instant download.
Play
Play BRSTM/BCSTM/BFSTM files in your browser with real-time FFT spectrum visualization and multi-track support.
Loop
Sample-accurate loop point editing. Set seamless loops for perfect game background music playback.
Popular Tools
MP3 to BRSTM
Convert MP3 to BRSTM for Wii games and Dolphin Emulator
WAV to BRSTM
Lossless WAV conversion for best quality BRSTM output
BRSTM to MP3
Extract audio from BRSTM files to standard playable format
MP3 to BFSTM
Convert MP3 to BFSTM for Wii U and Nintendo Switch
BRSTM Player
Play BRSTM/BCSTM/BFSTM files with spectrum visualizer
BCSTM Converter
Create BCSTM files for Nintendo 3DS games and homebrew