⚡ 100% Client-Side DSP • Zero File Upload to Server • Complete Privacy

BPM & Musical Key Analyzer

Upload any audio track to instantly extract exact BPM (tempo), rhythmic swing, musical key, and Camelot wheel harmonic mixing codes with high-precision digital signal processing.

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Drop an audio file here, or browse files

Supports MP3, WAV, FLAC, M4A, AAC, and OGG (Up to 150MB)

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Analysis Result 98% Confidence

Track Title

Tempo (BPM) Live Praise & Worship

124.0

Beats Per Minute

Adjust:

Musical Key Minor Tonality

A minor

Root Tonic & Scale

Relative Key: C Major

Camelot Wheel Harmonic Mixing

1m OpenKey

Harmonic Match Codes:

7A 9A 8B

Track Specs Telemetry

Duration: 3:45

Sample Rate: 44,100 Hz

Channels: Stereo (2ch)

Dynamic RMS: -12.4 dB

Worship Groove Swing: 54%

Waveform & Beat Grid

Metronome Sync

Click anywhere on the waveform to seek • Beat grid lines are automatically calculated at the detected tempo

🕊️ Worship Harmonic Key Transition Guide Camelot & Fifths Rule

Praise tracks with keys matching 7A, 8A, 9A, or 8B can transition seamlessly during worship services without key clashing or musical dissonance.

Browse Worship Artists Matching This Tempo ➔

Audio Engineering & Music Theory Guide

The Science of Tempo Tracking, Key Profiling, and Harmonic Mixing

Understanding the mathematical principles of audio digital signal processing (DSP), rhythmic onset detection, and pitch-class chromagrams enables DJs, producers, and live sound engineers to craft flawless sets and coherent studio productions.

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How BPM Induction Works

Our engine combines Dixon's Beatroot agent hypothesis with multi-threshold biquad lowpass filtering (150 Hz cutoff) to isolate transient kick impacts. By evaluating inter-onset interval (IOI) histograms through periodic autocorrelation, the algorithm accurately identifies the fundamental tempo while preventing common 2x octave octave errors.

Zero server uploads (100% client-side DSP)
Sub-beat grid calculation across the entire waveform
Energy RMS dynamic headroom evaluation

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Chromagram & Key Detection

Musical key is determined via a 12-semitone Pitch Class Profile (Chromagram). Short-time Fourier Transforms extract harmonic energy across all octaves from C2 (65.4 Hz) to B5 (987.8 Hz). The resulting vector is correlated against Krumhansl-Schmuckler cognitive tonal profiles to extract the root tonic and major/minor mode.

Krumhansl-Kessler cognitive correlation matrix
Camelot Wheel & OpenKey harmonic notation
Relative major/minor pair computation

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Harmonic Transitions & Modulations

Smooth worship sets rely on complementary musical frequencies to prevent jarring harmonic friction between praise anthems and intimate worship ballads. On the Camelot Wheel and Circle of Fifths, shifting by one step (e.g. 8A to 7A or 9A) or moving between relative major and minor guarantees musical peace and natural elevation.

Lift Key: step up a semitone or fifth for climactic praise
Relative Minor Pivot: transition from praise to contemplation
Zero dissonance during live choral and band crossfades

African Sacred & Gospel Music Tempo & Harmonic Directory

Reference tempo ranges, signature rhythmic characteristics, and typical key choices across sacred and gospel traditions.

Worship Director Reference

Tradition & Style	Typical BPM Range	Groove & Swing Profile	Harmonic Tendency
Contemporary Praise & Worship	68 – 76 BPM	Reverent 4/4 ballad pacing, dynamic swelling pads, Rhodes electric piano warmth	Major keys (G, D, C, E) & Em
African Choral & Sacred Hymnody	80 – 95 BPM	4-part SATB vocal polyphony, cathedral acoustic sustain, congregational call-and-response	Vocal resonance (F, Bb, Eb, Ab)
Traditional African Gospel & Zion Rhythms	108 – 118 BPM	Driving bass drum foundation, syncopated handclaps, acoustic bass gallop	Modal minor & blues (Am, Dm, Em)
High-Praise Celebration & Clapping Praise	120 – 132 BPM	Energetic brass fanfare, syncopated drum breaks, collective clapping praise pocket	Bright celebratory major (Bb, Eb, F, G)
Sacred Instrumental & Brass Ensembles	100 – 114 BPM	Gospel saxophone leads, trumpet section countermelodies, B3 Hammond organ swells	Gospel blues & 2-5-1 pivots (C, F, Bb)

Frequently Asked Questions (FAQ)

Are my audio files uploaded to any server during analysis?

No. All audio processing runs 100% locally inside your web browser using client-side Web Audio API and OfflineAudioContext. Your audio data never leaves your device, guaranteeing total privacy for unreleased tracks, dubplates, and exclusive stems.

How does the algorithm handle songs with variable tempo or live drummers?

The engine calculates both the overall global average BPM and creates individual beat markers across the entire track length. If a live drummer fluctuates slightly, the displayed BPM represents the mathematical median of the strongest recurrent inter-onset intervals.

Why do some songs display at double or half their expected BPM?

In music production, drum patterns with half-time snares (e.g. trap beats at 140 BPM with snares on beat 3) can mathematically resemble 70 BPM. You can use the quick "/2" and "x2" buttons next to the detected BPM display to immediately toggle between half-time and double-time representations.

What is Sacred Micro-timing & Praise Swing and how is it measured?

Straight electronic music quantizes beats exactly at 50% (equal spacing between 16th notes). African sacred music traditions—including church congregation clapping and choral polyphony—introduce organic micro-timing shifts where alternate subdivisions delay by 3% to 8%, creating an uplifting, human 'praise pocket' between 52% and 58%. Our DSP engine calculates this micro-timing offset directly from transient onset spacing.