What the key is and why it matters
A key is the set of notes a song is built around, plus one note that feels like home, called the tonic. A song in C major mostly uses the white keys of a piano and settles on C. A song in A minor uses the same notes but settles on A.
- Singers pick a key that fits their range.
- Producers and DJs mix tracks that are in the same or related keys so they do not clash.
- Guitarists and pianists use the key to choose chords and scales to play over.
- Songwriters transpose a song up or down to find a comfortable key.
Method 1: the free analyzer
The analyzer takes a stretch of up to 90 seconds from the middle of the file and measures how much energy falls on each of the twelve notes. It then compares that profile to standard major and minor key profiles (Krumhansl profiles) and picks the closest match. The run happens in your browser, the file is never uploaded, and there is no limit.
The Key card shows the best match and a runner-up, because some songs fit two keys almost equally well. The confidence percentage tells you how clear the winner was. The 12-note chart shows the raw note energy, so you can sanity-check the answer: the tonic and its fifth are usually tall.
What the Camelot code means
DJs often use the Camelot system, which labels each key with a number from 1 to 12 and a letter. A is minor and B is major. Keys with neighbouring numbers, or the same number with the other letter, blend well. The tool shows this code next to the key so you can plan a mix.
| Camelot code | Key | Blends well with |
|---|---|---|
| 8A | A minor | 7A, 9A, 8B |
| 8B | C major | 7B, 9B, 8A |
| 9A | E minor | 8A, 10A, 9B |
| 5A | C minor | 4A, 6A, 5B |
These pairs follow the standard Camelot wheel. Harmonic mixing is a guideline and not a guarantee, so trust your ears too.
Method 2: find it by ear
You do not need software. Play the song with a piano, guitar or a phone keyboard app, and follow these steps.
- Hum or hold a note while the song plays and move until one note feels like home, especially at the end of the song. That is the tonic.
- Play the third note above it. Four semitones up (C to E) sounds bright, which suggests major. Three semitones up (A to C) sounds darker, which suggests minor.
- Check the first and last chords of the song. They are often the tonic chord.
- Confirm by playing the scale of your guess along with the song.
Other tools and when they help
| Method | Good for | Trade-off |
|---|---|---|
| Free browser analyzer | Fast, private, unlimited | A wrong guess is possible on songs that modulate |
| By ear with an instrument | Learning and checking | Needs some ear training |
| DAW key detection | Producers already in a project | Depends on the DAW; not verified here |
| Chord chart sites | Popular songs | Quality and accuracy vary; not verified here |
Why results can be off
- Relative keys share notes. C major and A minor use the same notes, so they are the most common mix-up. Check the runner-up.
- Songs that change key, or move through many keys, do not have one answer. The tool reports the dominant key in the section it analyzed.
- Percussion-heavy or atonal tracks have little pitch information, so confidence will be low.
- Tuning that is slightly off from standard pitch can nudge a result between neighbouring notes.
If you want to change the key after you find it, use the pitch changer to shift the song up or down by semitones, and the BPM finder to get the tempo as well.
Frequently asked questions
How do I find the key of a song for free?
Drop the file into TuneSplit's BPM and key finder. It is free, unlimited and runs in your browser, so nothing is uploaded. It shows the key, a Camelot code and a confidence score.
How accurate is the key finder?
It works best on songs with clear harmony and a steady key. It shows a runner-up and a confidence percentage because some songs fit two keys, especially relative major and minor.
What is the Camelot code?
A label from 1A to 12B that DJs use to find keys that mix well together. A is minor and B is major, and neighbouring codes blend well.
Can I find the key on my phone?
Yes. The tool runs in a mobile browser: tap the upload box, choose a song and read the Key card.
Does it upload my music?
No. The analysis runs on your own device and the file never leaves it.
How can I find a song's key without a tool?
Find the note that feels like home, then test whether the third above it sounds bright (major) or dark (minor). The last chord of the song is usually the tonic.