Perfect First (Key, Tonic)
minor Second
Major Second
minor Third (rel Major, if minor chord)
Major Third (rel Major, if minor chord)
Perfect Fourth (Subdominant)
Tritone (Devil's Interval)
Perfect Fifth (Dominant)
minor Sixth (rel minor, if Major chord)
Major Sixth (rel minor, if Major chord)
minor Seventh
Major Seventh
NPCs.
Facts worth knowing:
The increment/decrement degree for a full 12-step octave (\sqrt[12]{2} or 1.059463 or the twelvth square of two).
The third interval normally determines whether a scale is major or minor.