BPM and key of whatever's playing.
KeyBee listens to your computer's sound output and puts the tempo and key in your menu bar. Spotify, YouTube, a DJ deck, a reference track in your DAW — if you can hear it, KeyBee reads it.
macOS 13+ · Windows 10 / 11 · iPhone
What you see, second by second
Press play. KeyBee shows the tempo first, then the key, and turns green once its last five readings agree.
- 0 s♪Listening
- 3 s128 ⋯Tempo first
- 4 s128 AmKey in
- 8 s128 AmFive readings agree
- Green
- Recent readings agree.
- Yellow
- Mostly agree.
- Red
- Still settling, or there's no clear beat — speech, ambience.
- Camelot and mix keys
- Show keys as 8A instead of Am, and see the three keys that blend cleanly with the one playing.
- Half and double
- If a track reads as 87 and you count 174, tap ×2. It resets on the next track.
- Track names
- Titles come from Spotify and other players. When there's no title, KeyBee can recognize the song.
- History and export
- Each confirmed reading is kept with its track. Copy a line, or export the set as CSV or Markdown.
- New track
- Mixed into something new and the old reading is hanging on? One click starts a fresh read.
- Out of the way
- Works only while sound is playing. No account, no sign-in. English, 한국어, 日本語, 中文, Español.
On iPhone: a booth clock that knows the key
The iPhone app listens through the microphone. Stand it next to the decks and it becomes your set clock; leave it on through the night and it remembers every track.
Turn it sideways for the set
- A big clock with BPM and key underneath — or flip it, with BPM and key big.
- Set timer for 30, 45, 60, 90 or 120 minutes. It turns yellow 10 minutes before the end and red at 5.
- Tap anywhere to start. Resetting takes two taps, so a stray hand can't wipe your set time.
- The screen stays on, and the timer keeps running even if the app is closed.
“What was that track?”
- Leave KeyBee listening. Every song it recognizes is saved with its BPM and key — nothing to press.
- Grouped by night, not by date, so a set that runs past midnight stays together.
- Heart the ones worth digging for later, then export a night or your liked tracks as text.
- Keeps listening on the Lock Screen and in the Dynamic Island while you use other apps.
Download
Questions
Does it use my microphone?
On Mac and Windows, no. It reads the sound your computer is already playing, so room noise doesn't get in. On iPhone it listens through the microphone.
Does my audio leave the computer?
Tempo and key are worked out on your device. If song recognition is on, a short audio fingerprint — not the recording — is sent to identify the track. You can turn it off in settings.
Which apps does it work with?
Anything that plays through the system output: streaming apps, browsers, rekordbox, Serato, Traktor, Ableton Live. On Windows it follows the default output device, so plugging in headphones doesn't break it.
Windows warned me about the download.
New apps from small publishers can trigger SmartScreen. Choose “More info”, then “Run anyway”. KeyBee installs for your user only and never asks for administrator rights.
How do updates work?
On Windows, KeyBee checks for a new version and installs it when nothing has played for ten minutes, so it never restarts in the middle of a set. Mac and iPhone update through the App Store.