Many recipes call for a specific amount of sliced, chopped or diced onion (usually measured in cups). But how many onions of what size do you need to get, say, ¼ cup of finely diced onion? This guide will help you find out.
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About this guide:
This guide lists how many slices and how many cups of sliced, rough-chopped, medium-diced or finely diced (minced) onion you get from different-sized whole onions. The tables below allow you to easily calculate how many onions of what size you need to get however many cups of cut onion you need.
Different onion cuts:
The tables below list amounts for five different cuts of onion:
- sliced crosswise (to get rings)
- sliced lengthwise (to get sliced onion)
- rough-chopped
- medium-diced
- finely diced (minced)
Sliced onion:
You can slice an onion crosswise to get rings or lengthwise (root to stem) to get sliced onion. The number of slices and cups of sliced onion listed in the tables below is for ⅛ inch-thick slices.
NOTE: Slicing an onion lengthwise is a great cut for caramelizing onion. Find a conversion of cups of sliced onion to cups of caramelized onion below.
Rough-chopped onion:
The amounts for rough-chopped onions listed in the tables below are for chunks of onion that measure about ½ inch per side.
Medium-diced onion:
The amounts for medium-diced onions listed in the tables below are for chunks of onion that measure about ¼ inch per side.
Finely diced onion (minced):
The amounts for finely diced onions listed in the tables below are for chunks of onion that measure about ⅛ inch per side.
How many cups does a small onion yield:
The measurements below are for one small onion (4 to 5 ounces and about 2 ¼ inches in diameter.) This is about the size of a lemon.
| Sliced crosswise (⅛th-inch thick): | Sliced lengthwise (⅛th-inch thick): | Rough-chopped (½-inch per side): | Medium diced (¼-inch per side): | Finely diced (⅛th-inch per side): |
|---|---|---|---|---|
| about 10 slices | about 1 cup (packed) | about 1 cup | about 1 cup | about ¾ cup |
How many cups does a medium-large onion yield:
The measurements below are for one medium-large onion (10 to 11 ounces and about 3 ¼ inches in diameter.) This is about the size of a Granny Smith apple.
| Sliced crosswise (⅛th-inch thick): | Sliced lengthwise (⅛th-inch thick): | Rough-chopped (½-inch per side): | Medium diced (¼-inch per side): | Finely diced (⅛th-inch per side): |
|---|---|---|---|---|
| about 14 slices | about 2 ¼ cups (packed) | about 2 cups | about 2 cups | about 1 ½ cups |
How many cups does a large onion yield:
The measurements below are for one large onion (13 to 14 ounces and about 3 ½ inches in diameter.) This is about the size of a small grapefruit.
| Sliced crosswise (⅛th-inch thick): | Sliced lengthwise (⅛th-inch thick): | Rough-chopped (½-inch per side): | Medium diced (¼-inch per side): | Finely diced (⅛th-inch per side): |
|---|---|---|---|---|
| about 14 slices | about 3 ½ cups (packed) | about 2 ¾ cups | about 2 ¾ cups | about 2 cups |
Cups of raw, sliced onion to cups of caramelized onion conversion:
2 cups (packed) raw, sliced onion will yield about ⅓ cup caramelized onion. (For this experiment I caramelized the sliced onion in 1 ½ tablespoons of butter in a cast iron pan.)
Elizabeth says
Thanks for the information. I often have bags of frozen chopped onions, but recipes always read, "one onion" etc. Now I can measure out my frozen chopped onions.
Nicole B. says
You're very welcome, Elizabeth! I'm so glad you're finding the guide useful.
M G Mancuso says
Love this article. Very helpful and easy to use. I'm keeping it in my Cookbook.
Nicole B. says
That's wonderful to hear!!
Linda Brown says
Thank you for the supper information on onions. No more guessing
for. I wish we could print out your information
Nicole B. says
You're welcome, Linda! And thank you for the feedback, it's much appreciated. I'll think about how best to present the info in pdf format so that it can be printed.