One medium banana has about 105 calories, and most people mean this size when they ask about “one banana.”

Quick Scoop

  • Small banana: about 80–90 calories (around 15 cm / 6 inches).
  • Medium banana: about 100–105 calories (about 100–120 g).
  • Large banana: about 120–135 calories.
  • Per 100 g of banana: roughly 89–108 calories, depending on the source and ripeness.

So if you grabbed a typical “medium” banana today, you can safely count it as roughly 100–105 calories.

Information gathered from public forums or data available on the internet and portrayed here.