The interval — the distance between two notes — is the building block of melodies and chords. If you can recognize intervals by ear, you can pick out melodies without sheet music, play more in tune and understand what you are playing.
In this game, you hear two notes and identify the interval. The level progression starts with clear contrasts, such as thirds and fifths, and refines your listening until it covers every interval within the octave — first melodic (notes in sequence), then harmonic (notes played together), which require separating the sounds inside a single attack.
Ranked mode tracks your progress level by level; free mode lets you choose exactly which intervals to practice — useful for attacking the classic mix-ups, like major third versus minor third.
Ear training rewards regularity, not marathons: a few minutes a day build more than an hour once a week. The game runs in the browser, nothing to install.