In Mario Kart 8 / Mario Kart 8 Deluxe , coins mainly increase your top speed a little bit and help you unlock kart parts and customization items as you collect more over time.

What coins do

  • Speed boost: Each coin gives a small speed increase, and the benefit builds up until it caps at 10 coins on the track.
  • Unlockables: Your total coin count unlocks new karts, bikes, wheels, gliders, and other parts as you hit milestones.
  • Race advantage: Keeping a healthy coin count matters because getting hit can make you lose coins, which means losing a bit of speed.

Quick tip

If you’re racing, try to stay near 10 coins during the race so you keep the speed benefit while still grabbing more for unlocks later.

If you want, I can also give you a super short “how many coins unlock everything” guide for Mario Kart 8 Deluxe.