- Required Problems: 20
- Demo version: Your score will not be saved
- Score 90% or better for full points
- Time Limit: 5 Minutes

Identify each interval interval by its size. If the interval is a unison/prime, a fourth, a fifth, or an octave, it can be perfect. If the interval is a second, third, sixth, or seventh it cannot.

*If the time limit is stressful, try Practice Mode.