Find the home note
Hum or play notes along with the track until one sounds like the place the music wants to rest. That is usually the tonic. It is often the bass note at the end of a phrase.
Major or minor?
Play the third above that note. If the major third sounds bright and settled, it is probably major. If the minor third sounds darker and more serious, it is probably minor.
Check the relative key
Every major key has a relative minor that uses the same notes, three semitones lower: C major and A minor, G major and E minor, F major and D minor. Software often gets the pair mixed up, so if the shown key sounds wrong, try its relative.
Use the estimate as a clue
The keys on this site are estimated by software. Use them to narrow the search: if it says A minor, test A, C and E first.
Mind the tuning
Some tracks sit a little sharp or flat of standard tuning. If your instrument sounds slightly off, tune to the track instead of the other way round.
Quick answers
How reliable are the keys shown?
Mostly right, sometimes a relative key away, and some tracks have no clear key. They are a starting point.
Can I find tracks in a key?
Yes. Open the keys page, pick a key on the wheel and you will see every track estimated to be in it.
