Debuting his new look on Instagram on Wednesday 16 March, the radio presenter and former-X Factor judge wrote: "Me dad's gonna go mad."
To help Grimmy on his quest for platinum hair, Fudge Professional were on hand with its Clean Blonde Violet Toning Shampoo and Conditioner (both £11.95).
Want to copy his new 'do? Tracy Hayes, global head of technical colour for the brand said: "Nick's cool blonde hue is very high fashion, but with high fashion comes high maintenance.
"Violet toned shampoo and conditioner are must-haves for anyone wanting to achieve platinum tones as it’s essential to eliminate any brassiness or yellow tones that come naturally from salon colour fade.
"Dark hair like Nick's that has been lightened so dramatically is the most prone to brassiness."