Beatkey: BPM & Key Finder

Point your iPhone at any song and Beatkey tells you the tempo, the key, and the Camelot code — analyzed entirely on your iPhone using Apple's new Music Understanding technology in iOS 27. Nothing is uploaded, nothing needs an internet connection.

LISTEN
Tap record, play music near your phone, and watch a live level meter while Beatkey listens. Stop, and get BPM, loudness, and half-time/double-time alternates in seconds — plus key + mode (like "A minor") with the unlock.

IMPORT (with the unlock)
Analyze any track already on your iPhone — mp3, m4a, wav, or aiff — straight from the Files app.

CAMELOT WHEEL (with the unlock)
Every key comes with its Camelot code (like "8A") for harmonic mixing, shown on a Camelot-style key ring so you can see compatible keys at a glance.

TAP TEMPO, ALWAYS AVAILABLE
No music understanding needed — tap along to anything and get an instant BPM reading, on any device.

YOUR HISTORY
Your five most recent analyses are free; the unlock keeps every one. Each is saved locally: rename it, search or sort by BPM or key, and share a result as text. Delete anything, any time.

HOW ACCURATE IS IT?
Beatkey is built directly on Apple's on-device Music Understanding framework, new in iOS 27 — the same technology built into iOS itself. It reads tempo, key, and loudness; it doesn't guess. A "steady" vs. "variable" tempo reading is Beatkey's own on-device estimate of how consistent the beat is, shown honestly as an estimate, not a score from Apple.

PRIVACY, BY DESIGN
Audio never leaves your iPhone. There are no accounts, no servers, and no analytics of any kind — Beatkey simply has nowhere to send your data.

FREE TO TRY, ONE-TIME UNLOCK
Listening and tap tempo are free — live BPM from any song, plus your five most recent analyses. One optional purchase ($2.99, once — never a subscription) unlocks file import, musical key with Camelot codes, and unlimited history. No ads, ever.

Requires iOS 27 or later.