SongDecode — Song Key & BPM Finder with URL (Online)

Find BPM of a Song with URL (Online)

Detect the exact tempo and beat structure of any song directly from a browser tab URL. No need to download lossy MP3 files or install desktop software—SongDecode decodes the digital audio stream live with zero latency.

Find Key of a Song & Camelot Key Finder

Detect the tonal center, scale, and Camelot wheel key of any track instantly. Whether you need the song key finder for DJ harmonic mixing or music production, SongDecode delivers real-time key confidence ratings.

Completely Free — No Login or Signup Needed

SongDecode is 100% free with no registration, email signup, or subscriptions required. Every Fast Fourier Transform (FFT) and key detection calculation runs client-side in your browser's RAM for total privacy.

Camelot Key Finder for Harmonic DJ Sets

Harmonic mixing relies on matching compatible musical keys. SongDecode automatically translates traditional keys (like C Major or A Minor) into Camelot wheel coordinates (like 8B or 8A). DJs can transition between adjacent Camelot numbers to raise energy or create seamless, dissonant-free blends without touching a key wheel chart.

• Compatible Key Discovery: Identify 1-step Camelot transitions (+1, -1, or relative major/minor) live as audio streams.
• Real-Time Key Stability: Measures tonal persistence across verses, builds, and drops to confirm key shifts.
• DJ Software Ready: Use detected Camelot keys directly in Rekordbox, Serato DJ, Traktor, and VirtualDJ.

12-Semitone Real-Time Chromagram Profile

Our digital signal processing engine maps incoming audio onto an instantaneous 12-semitone pitch profile (C through B). Watch which notes and harmonic overtone clusters dominate the mix as the song progresses.

• Tonal Center Visualization: See real-time chroma energy across all 12 musical semitones simultaneously.
• Scale & Mode Identification: Distinguishes major, natural minor, harmonic minor, and dorian modes.
• Polyphonic Chord Tracking: Detects complex triads, 7th chords, and synth pads with confidence scoring.

1. Real-Time BPM Counter & Live Tempo Finder

Unlike static BPM checkers that guess from metadata, SongDecode calculates tempo dynamically using digital signal processing on the live audio waveform. It isolates low-frequency kick drum transients, 808 subs, and snare rimshots to calculate the exact beats per minute (BPM).

2. Dynamic Tempo Gauge (60 to 180+ BPM)

A full-width tempo gauge visualizes where your track sits across the musical tempo spectrum—from slow ballads (60-80 BPM) and boom-bap hip-hop (90 BPM) to house (120-128 BPM), trap/dubstep (140 BPM), and fast drum & bass (174+ BPM).

3. 3-Second Rolling Moving Average

Eliminates transient misfires and tempo jitter with a continuous 3-second rolling window. Track whether a song was recorded to a strict studio click-track or features natural human drummer tempo drift.

4. DJ Beat Grid Stability & Audio Telemetry

Provides instant readouts for grid stability, bar intervals, dynamic crest factors, and loudness (LUFS), giving DJs, remixers, and audio engineers everything needed to sync tracks and calibrate mix levels.

Bass & Sub-Bass (20 - 60 Hz)

Tracks deep 808 subs, kick fundamental thumps, and analog bass synthesis. Evaluates dynamic kick-to-bass ducking ratios to measure punch clarity versus muddy low-end buildup.

Beats, Drums & Transients (60 - 250 Hz)

Measures transient attack sharpness, snare cracking energy, acoustic drum kits, hi-hat syncopation, and tempo stability across verse-chorus transitions with sub-millisecond precision.

Trebles & Vocal Presence (1 - 4 kHz)

Analyzes lead vocals, backing harmonies, guitar solos, brass blasts, and melodic synth hooks, checking harmonic overtone balance and phase correlation.

Mouth Organ, Harmonica & Reeds

Dedicated spectral recognition for mouth organ (harmonica), accordion reeds, blues harps, melodicas, and bagpipes, capturing expressive pitch bends and reed vibrational overtones.

Global Ethnic Instruments

150+ acoustic profiles identifying sitars, tablas, djembe, Celtic bagpipes, Japanese koto, shakuhachi flutes, Middle Eastern oud, and Caribbean steelpans in active world grooves.

Air & High-Frequency Sparkle (4 - 20 kHz)

Monitors crash cymbals, shaker rustle, spatial acoustic reverb tails, and high-frequency sparkle essential for professional mastering and balanced DJ track selection.