Play BCSTM files in your browser
The looping music of 3DS, Wii U and Switch games. Play a BCSTM or BFSTM right here, loop and all, and keep it as an MP3 or WAV. Nothing leaves your device.
Or drop it anywhere on this page
What you'll see
Your game's sound plays the moment it opens, twice through its loop and then a fade, its whole waveform across your screen.
- Its whole waveform • Press or drag to jump
- Back and ahead 10 seconds • Half, 1.5× or double speed
- Show tags • Codec, loop, sample rate and channels
- Export • Save as MP3 or WAV
About BCSTM
Nintendo carried the Wii's BRSTM on to its next consoles: BCSTM, C for CTR, the 3DS's code name, and BFSTM, F for Cafe, the Wii U's, which the Switch kept. Games stream their music from them, and fans make them as custom music for games like Mario Kart 7 and Mario Kart 8.
Both hold Nintendo's DSP-ADPCM, 4 bits a sample, IMA ADPCM or PCM, in blocks for each channel, with the loop in their header, so a level's music plays on seamlessly. A BCSTM is little endian, for the 3DS, and a BFSTM big endian on the Wii U and little endian on the Switch.
Filepeek plays them in your browser with vgmstream, twice through the loop and then a fade, with their waveform, speeds and tags, and Export saves them as MP3 or WAV.
3DS, Wii U and Switch music stream
.bcstm • .bfstm
Format
- MIME type
- application/octet-stream
- Made by
- Nintendo
- Released
- 2011
Inside the file
- Audio
- DSP-ADPCM, IMA ADPCM or PCM
- Loop
- Where the music starts over
- Consoles
- 3DS, Wii U and Switch
- Kin
- BRSTM, on the Wii
Opens in every browser
Filepeek plays BCSTM and BFSTM files in Chrome, Edge, Firefox and Safari. No browser plays them by itself.
- YouChromePlays through Filepeek
- YouEdgePlays through Filepeek
- YouFirefoxPlays through Filepeek
- YouSafariPlays through Filepeek
Apps that open BCSTM
- Windowsfoobar2000 with vgmstream, free
- MacNo app built in plays it • vgmstream-cli, from Homebrew, turns it into a WAV
- iPhone and iPadNo app built in plays it
- AndroidNo app built in plays it • An MP3 saved here plays anywhere
Questions
How do I play a BCSTM file?
Drop it on this page or choose Peek a BCSTM. It plays in your browser, twice through its loop and then a 5 second fade, the way a game loops its music.
Can I turn a BCSTM into an MP3?
Yes. Choose Export, then Save as MP3 or WAV, and the sound is saved as it plays here, loop and fade included.
What is the difference between BCSTM and BFSTM?
BCSTM is the 3DS's and BFSTM the Wii U's and the Switch's, with the same blocks inside. Filepeek plays both, and the Wii's BRSTM too.
Why does my custom track loop at the wrong place?
The loop is wherever the tool that made it put it, in the header. Filepeek plays it as the game would, from the start to the end and back to the loop.