Convert Onion from Whole Onions to Ounces
Use the tool below to convert onion from Whole Onions to Ounces.
How many ounces is one medium onion?
One medium onion is about 3.88 ounces. A small onion is about 2.47 ounces and a large one about 5.29 ounces, so set the size selector to match what you have. Use the converter above for any amount, or the chart below for the most common quantities.
Related Onion Ingredients
Already chopping? The chopped onion converter moves straight between cups, grams, and spoons of prepped onion. See our Chopped Onion converter.
Need a milder, more delicate allium? Shallots (20–60 g) suit dressings and pan sauces. See our Shallot converter.
Spring onions (10–25 g) are tender and herbaceous, great raw or as a garnish. See our Spring Onion converter.
Mincing garlic for the same dish? Garlic cloves (2–7 g) bring pungent bite where onion brings sweet body. See our Garlic converter.
Want a crisp, peppery bite? Radishes (8–25 g) are sharp and crunchy, good raw in slaws or quick pickles. See our Radish converter.
Out of onion? See onion substitutes →
Onion converter tool
Enter an amount, pick your units, and set the size for counting whole onions.
Result
3.88 ozOnion Calculators & Kitchen Tools
Working with onion? These tools handle the jobs a converter cannot.
- Oven to Air Fryer Converter Match the temperature and time when you swap the oven for an air fryer, fan oven, or slow cooker.
- Recipe Scaler Scale any recipe up or down and keep every ingredient in ratio.
Common Onion conversions
Quick reference for onion at medium size. Switch the size in the converter above for small or large.
| onions | Ounces |
|---|---|
| 1 onion | 3.88 oz |
| 2 onions | 7.76 oz |
| 3 onions | 11.64 oz |
| 4 onions | 15.52 oz |
| 5 onions | 19.4 oz |
| 6 onions | 23.28 oz |
For the reverse conversion, see how many onions are in an ounce.
Frequently Asked Questions
- How many ounces is one medium onion?
- One medium onion is about 3.88 ounces, a small one about 2.47 ounces and a large one about 5.29 ounces. Onions vary in size, which is the main reason a recipe that counts onions can still vary in weight. Set the size selector to match what you have, then read the exact figure for any count above. Open the onion converter
- How many ounces is 2 onions?
- 2 onions are about 7.76 ounces. The ratio is fixed, so one medium onion is 3.88 ounces and the figure scales in a straight line as you multiply or divide. Scaling a recipe up or down keeps the same proportion, so work from whichever amount your recipe lists. Use the converter above for any other quantity of onion.
- How many ounces is 3 onions?
- 3 onions are about 11.64 ounces. The ratio is fixed, so one medium onion is 3.88 ounces and the figure scales in a straight line as you multiply or divide. Scaling a recipe up or down keeps the same proportion, so work from whichever amount your recipe lists. Use the converter above for any other quantity of onion.