Pistachio sizes explained: what “nuts per ounce” means
Pistachios are graded by how many in-shell nuts fit into one ounce. The lower the number, the bigger the nut. Here is how the grades work and how to choose the right one.
What does “nuts per ounce” mean?
One ounce is about 28.35 grams. A size grade such as 22–24 tells you that a 28-gram sample contains 22 to 24 in-shell pistachios. It is the standard way Iranian pistachios are sized and traded, and it lets buyers compare lots without seeing them.
Lower number, bigger nut
A 20–22 pistachio is much larger than a 30–32. Fewer nuts are needed to make up the same weight, so each one is heavier and fuller. As a rough guide, a kilo of 20–22 holds around 700 to 780 nuts, while a kilo of 30–32 holds around 1,060 to 1,130.
The common size grades
- 20–22 and 22–24: the largest grades, chosen for premium snacking and gift packs.
- 24–26 and 26–28: large and well-balanced, a popular choice for quality retail.
- 28–30 and 30–32: smaller and uniform, good value for roasting, mixes and everyday snacking.
Size depends on the variety
Each Iranian variety tends to fall into its own range. Kalleh Ghoochi is large and round and usually sits in the biggest grades. Akbari is extra-long and also grades large. Ahmad Aghaei is long and slender, and Fandoghi is round and compact, typically in the smaller grades. Season, orchard and harvest all play a part, so every lot is measured on its own.
Which size should you choose?
- For gift boxes and premium shelves: 20–22 to 24–26, ideally Kalleh Ghoochi or Akbari.
- For roasted & salted snacks: a uniform grade matters more than the biggest size, so every nut roasts evenly.
- For pastry and ice cream: size matters less; kernel colour does, which is why confectioners often choose Ahmad Aghaei kernels.
Size is only part of quality
A big nut is not automatically a good one. Look at the open-shell rate, moisture, shell colour and kernel colour too. Our guide to pistachio quality explains what to check before you buy.