A tablespoon of peanut butter weighs 0.579 oz (16.4 g) and has a volume of 1 tbsp (14.8 mL). In plain language, this amount is about the size of a grape.

In kitchen measures
3 teaspoons
3 tsp · 1 tbsp · 0.063 cups
about the size of a grape
Peanut butter typically ranges 1.08–1.14 g/mL depending on how it's packed. A firmly packed scoop weighs more.