Katy Perry and John Mayer's relationship isn't serious.

While the 28-year-old 'Firework' singer recently reconciled with the 35-year-old singer/songwriter after splitting for the second time in March, they have reportedly decided they are not ready to commit to each other.

A source told E! News: ''They are just hanging out. They are not putting a label on it.''

Following their latest split, Katy was said to be releasing her ''anger'' over the failed romance by going spinning and soothing her brain'' at Los Angeles' candlelit Soul Sanctuary spa.

A source said: ''Katy believes the workouts have really helped her with releasing anger, stress and tension from the split and the sanctuary has been soothing her brain.

''A few years ago she would have released the energy by hitting the clubs and dancing the night away. But she's getting older now and wants to do things healthily.''

A close pal previously predicted that the on/off couple might reunite following their latest split.

The insider said: ''It's not over until it's over. You have to see how things play out.''