Kapi — Shrimp Paste Grades & Application / กะปิ

Coastal Thai throughout all regions — Southern (Klong Kone, Rayong) considered premium; Isaan uses pla raa as a regional equivalent

Kapi is fermented shrimp paste made from small krill or shrimp (Acetes species) mixed with salt and sun-dried over several days before being pounded and aged. It is the backbone of almost every Thai curry paste and many nam prik, providing umami depth, salinity, and a characteristic fermented complexity that cannot be replicated by fish sauce alone. Quality grades range from pale purple-grey, freshly made kapi (moist, strong) to deep purple-brown aged kapi (drier, more complex, less pungent when raw) to the almost-black kapi from Rayong and Klong Kone (prized for paste work). Kapi is always cooked before service — either roasted, fried in the curry paste, or wrapped in banana leaf and grilled.

Kapi anchors the umami foundation of paste-based dishes — it is the reason a Thai curry tastes categorically different from an Indian one despite sharing spice profiles.