One tablespoon of coriander seeds is a small amount that measures 1 tbsp (14.8 mL). When poured into a loose pile, it 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
Density estimated by AI from typical values. Coriander seeds typically ranges 0.32–0.45 g/mL depending on how it's packed. A firmly packed scoop weighs more.