How to Size Pistachio
Have you ever wondered how professionals determine the size and quality of pistachios? Fortunately, you can use the same simple, standardized method yourself. This method requires no special instruments—just a basic kitchen scale and a minute of your time.
In this guide, we will walk through a clear, four-step process. First, you measure a precise weight of pistachios. Next, you sort them into small, equal groups. Then, you count those groups to find your key number. Ultimately, this number reveals the size grade of your nuts, with a simple, consistent rule: a lower number indicates larger, higher-quality pistachios.
Step 1: Weigh a Fixed Amount
Take exactly 142 grams of in-shell pistachios. You can use a small kitchen scale for this. This weight is the starting point for everyone, so all comparisons are fair.
To get a true “ounce” size, your 142-gram sample must fairly represent the whole batch.
- Follow these 4 steps:
- Mix First: Gently shake or stir your main container of pistachios.
- Scoop Generously: Take a slightly larger amount (about 150–160g) from the mixed batch.
- Weigh & Trim: Place the scoop on your scale and remove nuts one by one until the scale reads exactly 142.0g.
- Why It Works: This method removes selection bias—your final sample is a true random mix, not just nuts from the top or bottom.
- Result: Your count will accurately reflect the average size of all the pistachios in your batch.
Step 2: Make Groups of Five
From your 142-gram pile, start counting the pistachios out loud. Put them into small piles or rows. Every time you count 5 pistachios, set that group aside. Keep doing this until you’ve sorted all the pistachios from the original 142 grams.
Step 3: Count the Groups
Now, look at all the groups of five you made. Simply count how many groups you have.
For example, you might end up with 22 groups, or 26 groups, or 30 groups.
Excellent question. When someone says pistachios are “18–20”, it means they are exceptionally large and premium—only about 90 to 100 individual nuts make up the standard 142-gram weight. Conversely, a size of “28–30” indicates a medium or commercial grade; these nuts are noticeably smaller, requiring about 140 to 150 of them to reach that same 142 grams. Simply put, the lower the number, the larger and more valuable the pistachio.
Step 4: This is your ounce number.
The number of groups you counted is called the “ounce” count in this system.
If you have 22 groups, your pistachios are a “22-ounce” size.
If you have 30 groups, your pistachios are a “30-ounce” size.