Tomato Conversions and Equivalents

How many fresh tomatoes equal one can?

Basket of tomatoes
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We've all been there—you begin to make a recipe and it calls for one pound of tomatoes. You don't own a food scale, so how are you supposed to know how many tomatoes to use? Or, maybe the recipe calls for canned tomatoes but you only have fresh—what exactly is the equivalent to 28 ounces? 

Luckily, there are methods for converting tomatoes from amount to weight, or fresh to canned. Charts laying out the equivalents of whole tomatoes to weight, whole tomatoes to cups, and canned to whole tomatoes and cups will make these conversions quick and easy.

But before we get to that, let's talk about how to choose the best tomatoes.

Selecting Top-Notch Tomatoes

Nowadays there are so many choices of types of tomatoes in the supermarket—cherry, grape, yellow, heirloom, vine-ripened, Campari, Kumato, beefsteak, and Roma, to name just a few. But no matter which variety you pick, it is important you know what to look for to assure that you're getting the best quality. There are three ways to determine whether a tomato is worth buying: appearance, feel, and smell. 

First, you want to look for tomatoes that have a deep, bright red color. Those that are "vine-ripened" may be your best bet since most tomatoes are harvested when still green and left to ripen in transport, which results in a pale, bland-tasting fruit. Also, check for any blemishes such as black spots—they may seem like nothing, but they could signal that the inside is rotting.

Next, hold the tomato—you want it to feel heavy in the hand.

A tomato with a bit of weight means that it is ripe and nice and juicy inside. Then give it a gentle squeeze. How much give is there? You want it to resist but not feel rock hard. Of course, you also don't want it to be a pile of mush.

The last step is to take a whiff. If you don't smell anything then you probably won't taste anything.

You want the tomato to have an earthy, sweet aroma that is somewhat strong. 

Of course, if the tomatoes are packaged in plastic wrap or containers touching and smelling will be impossible. If you can, avoid buying tomatoes that are pre-packaged, but if they are your only option just do the best you can.

Tomato Equivalents by Weight

This chart converts amounts of different tomatoes to weight—perfect when your recipe specifies pounds but you don't know the weight. 

 1 large tomato a little less than 1 pound
 3 medium globe tomatoes 1 pound
 8 small plum tomatoes 1 pound
 15 to 20 cherry tomatoes 1 pound


Converting Weight to Cups

If you purchased tomatoes using the grocery store scale, then you only have the weight to work from—but your recipe calls for cups of chopped tomatoes. This chart will help you realize the equivalents. 

 1 pound 1 1/2 cups chopped tomatoes
 1 pound 3 cups pureed
 2 1/2 pounds 3 cups chopped and drained
 2 cups chopped 1 pound
 2 1/2 pounds 2 1/2 cups seeded, chopped, and cooked


Canned Tomato Equivalents

Perhaps you made a last-minute decision to make a certain dish that calls for canned tomatoes, and you only have fresh tomatoes in the pantry. Or the recipe calls for cups of tomatoes and you are going to use canned.

Not to worry—this chart will sort it all out.

 1 cup canned tomatoes 1 1/2 cups fresh, chopped, cooked tomatoes
 1 (16-ounce) can 2 cups undrained, 1 cup drained
 1 (28-ounce) can 3 cups undrained, 2 1/2 cups drained
 1 (35-ounce) can 4 cups undrained, 2 1/2 to 3 cups drained
 1 (14.5-ounce) can 5 to 6 small tomatoes or about 1 pound


Other Equivalents

Whether it is a question of servings or how to substitute tomato sauce, these conversions will help you out in the kitchen.

 1/2 pound or 1 tomato 1 serving
 1 cup firmly packed chopped fresh tomato 1/2 cup tomato sauce plus 1/2 cup water
 1/2 cup of tomato paste plus 1/2 cup water 1 cup tomato sauce