How to Cut an Onion

From dicing to slicing, learn how to cut an onion.

Lisa Kingsley and Alex Loh Updated January 05, 2022

Credit: Casey Barber

From a sharp red onion to a milder, slightly sweet Vidalia, this important member of the allium family is a tasty addition to any recipe. Onions can be the star of a dish, like in our Caramelized Onion & Goat Cheese Toast, or they can be used as an aromatic, like in our Spinach, Feta & Rice Casserole. Before you can successfully cook with onions, you should first learn how to properly cut an onion. (And if you're worried about tearing up, check out these tips for cutting an onion without crying.)

Related: How to Store Onions

Credit: Casey Barber

How to Dice an Onion

Credit: Meredith Food Studios

Step 1

Cut off stem end, leaving root end intact, then cut the onion in half through the root end. Peel the onion.

Credit: Meredith Food Studios

Step 2

Place the flat end of one onion half on the cutting board. With the knife parallel to the cutting board, make one or two cuts lengthwise from the stem toward (but not through) the root end. (Stabilize the onion with your fingers on top and out of the path of the knife.)

Credit: Meredith Food Studios

Step 3

With your knife now perpendicular to the cutting board, make a series of lengthwise cuts through the onion half, from stem to root end. Cut crosswise into dice.

How to Slice an Onion

Credit: Meredith Food Studios

Step 1

Cut off root end.

Credit: Meredith Food Studios

Step 2

Cut off stem end.

Credit: Meredith Food Studios

Step 3

Peel the onion.

Credit: Meredith Food Studios

Step 4

Cut the onion in half lengthwise.

Credit: Meredith Food Studios

Step 5

Place the flat end of one onion half on the cutting board. Cut parallel to the grain of the onion from stem to root end, adjusting the cuts to the desired slice thickness.

How to Slice an Onion into Rings

Credit: Karla Conrad

Step 1

Cut off stem end, leaving root end intact. Peel the onion.

Credit: Karla Conrad

Step 2

Slice across the onion (widthwise) to create rings. Separate the onion into individual rings. Discard the root end. (To keep the onion from rolling when you slice, you can cut a small, flat spot to rest against the cutting board to help stabilize it.)