How much is one medium onion in cups?

One medium onion is 0.66 cups. The conversion scales in a straight line, so 2 onions is 1.32 cups and 3 onions is 1.98 cups. Multiply or divide that figure to match whatever your recipe needs, or use the converter above for an exact reading at any amount.

How much does one medium onion weigh?

One medium onion weighs about 110 grams. A small one is about 70 grams and a large one about 150 grams, so set the size selector to match what you actually have. The converter above and the chart above cover all sizes and units for any amount.

Convert Onion from Whole Onions

Use the tool below to convert onion from Whole Onions to the measurement that you need.

More about measuring Onion

How much is one medium onion?

One medium onion is 0.66 cups, about 110 grams. 2 onions is 1.32 cups and 3 onions is 1.98 cups. Use the converter below for any amount.

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 shallots in items.

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 cloves in items.

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.

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Onion sizeSize applies to whole onions (small / medium / large).

Result

0.66 cups

Onion Calculators & Kitchen Tools

Working with onion? These tools handle the jobs a converter cannot.

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Common Onion conversions

Quick reference for onion at medium size. Switch the size in the converter above for small or large.

onions	Cups (chopped)
1 onion	0.66 cups
2 onions	1.32 cups
3 onions	1.98 cups
4 onions	2.63 cups
5 onions	3.29 cups
6 onions	3.95 cups

Onion conversion chart

The chart below shows how whole onions (medium size) convert to cups, grams and ounces.

onions	cups	cups (US)	g	oz	lb	kg
1 onion	0.66 cups	0.69 cups (US)	110 g	3.88 oz	0.24 lb	0.11 kg
2 onions	1.32 cups	1.38 cups (US)	220 g	7.76 oz	0.49 lb	0.22 kg
3 onions	1.98 cups	2.06 cups (US)	330 g	11.64 oz	0.73 lb	0.33 kg
4 onions	2.63 cups	2.75 cups (US)	440 g	15.52 oz	0.97 lb	0.44 kg
5 onions	3.29 cups	3.44 cups (US)	550 g	19.4 oz	1.21 lb	0.55 kg

Frequently Asked Questions

How much is one medium onion?: One medium onion is 0.66 cups, or 110 grams. The ratio is fixed, so 2 onions is 1.32 cups and 3 onions is 1.98 cups. Use the converter above for any amount, or the chart above for the most common quantities. Open the onion converter
How much is one medium onion in cups?: One medium onion is 0.66 cups. The conversion scales in a straight line, so 2 onions is 1.32 cups and 3 onions is 1.98 cups. Multiply or divide that figure to match whatever your recipe needs, or use the converter above for an exact reading at any amount.
How much does one medium onion weigh?: One medium onion weighs about 110 grams. A small one is about 70 grams and a large one about 150 grams, so set the size selector to match what you actually have. The converter above and the chart above cover all sizes and units for any amount.

Onion measurement options

Choose from the following measurements to convert to