Key Detector
Estimate musical key and scale from a clip using chroma analysis — fully local.
Drop a file here or browse
MP3, WAV, FLAC, M4A, OGG — processed locally, never uploaded
Outer ring: major (B). Inner ring: minor (A). Highlighted keys are practical harmonic-mixing options around the detected key.
Music theory — —⌃
What it does
Musical key helps with harmonization, sampling, and DJ transitions. Key Detector estimates the most likely major or minor key from a clip by building a chroma profile (energy in each pitch class) and comparing it to classic major/minor templates such as Krumhansl–Schmuckler profiles. The method is transparent and local: an FFT-based chroma analysis followed by correlation with key profiles. It works best on harmonic material with a stable tonal center. Results are suggestions for practice and organization, not a substitute for careful listening on ambiguous or highly chromatic music.
How an audio key detector estimates key
A song’s key describes its tonal center and the major or minor scale that may organize its melody and harmony. Producers, instrumentalists, and DJs often use key estimates when arranging, practicing, sampling, or planning harmonic transitions.
This detector builds a chroma profile from the audio spectrum and compares the pitch-class energy with standard major and minor key templates. It works best on a clear melodic or harmonic passage. Drum-only audio, dense arrangements, modal music, and frequent key changes can produce uncertain or misleading estimates.
Get a more representative key estimate
For the clearest result, use a passage with sustained chords, a recognizable melody, or a stable harmonic center. A drum break, noisy transition, or very short one-note fragment may not contain enough pitch information for a confident estimate. Sections that modulate between keys can also produce competing results.
Key detection is especially helpful as a first reference when organizing samples, practicing songs, or exploring harmonic compatibility. Treat the result as a useful clue rather than an absolute label: modal, blues-based, or chromatic music may not fit neatly into a single major or minor profile.
How to use it
Choose a tonal section
Load a clip where chords or melody clearly outline a key. Avoid pure drums or noise-only segments.
Run key detection
Start analysis so the browser can compute chroma features and score major/minor profiles.
Inspect the top keys
The best-matching key is highlighted; nearby alternatives can appear when the music is ambiguous.
Combine with other tools
Use BPM Detector for tempo and Equalizer if the mix hides the harmonic content.
Tip: Analyze a few different sections if the song changes harmony. A chorus or verse with stable chords is often more informative than an intro or percussion-only break.
Questions about Key Detector
01What does a musical key tell you?+
A musical key describes the tonal center that a track tends to resolve around and the major or minor scale associated with it. Key Detector estimates that center from the pitch content of the audio.
02How does Key Detector find the key?+
The tool analyzes pitch-class energy across the audio, builds a chroma profile, and compares it with major and minor key profiles. It then ranks the strongest candidates and reports the best match.
03What is a Camelot code?+
Camelot notation maps major and minor keys to DJ-friendly numbers and A/B labels. The code makes it easier to spot nearby harmonic-mixing options, while the actual transition should still be checked by ear.
04What is the relative key?+
A major key and its relative minor share the same notes. For example, G major and E minor are relative keys. They can sound quite different even though they belong to the same pitch collection.
05How accurate is an online key detector?+
Confidence is a useful comparison signal, not a guarantee of correctness. Strongly tonal sections usually produce clearer results, while short clips, heavy percussion, modal music, modulation, or very chromatic arrangements can create close candidates.
06Can I analyze a track from My Library?+
Yes. Choose My Library in the source switcher and select a saved track. The stored audio is loaded into Key Detector locally, so you can analyze it without selecting the file again from your computer.