Gatwick Express operates a train from Hammersmith to Brighton every 30 minutes. Tickets cost $29 - $45 and the journey takes 54 min.
How to get from Hammersmith to Brighton
From Hammersmith (Dist&Picc Line) Underground Station Tube to London Victoria then train to Brighton. 1 h 22 min £27. From Hammersmith Bus Station line 295 bus to Clapham Junction then train to Brighton. 1 h 53 min £26. From Hammersmith drive to Brighton. 1 h 13 min £10.