Scaling a tomato recipe up or down is simple: multiply each amount by the new servings divided by the old servings. Swapping fresh tomatoes for canned takes a ratio, since about 1 pound of fresh, peeled tomatoes replaces a 14.5 ounce can. Use the converter below to scale a recipe or switch between fresh and canned.
Try a preset:
Your entries stay in your browser. Nothing is sent to a server or saved to an account. For plain weight, cup, and can unit conversions, use the Measurement Converter.
What Your Result Means: for a scaled recipe, the amount is your ingredient adjusted to the new serving count. For a fresh-and-canned swap, the figures are cooking equivalents, since canned tomatoes are peeled and packed, so fresh needs peeling and a little simmering to match.
How Do You Convert a Tomato Recipe?
Pick whether you want to scale a recipe by servings or swap fresh tomatoes for canned. For scaling, enter the tomato amount and the old and new serving counts. For a swap, enter what you have and the tool shows the equivalents.
- Choose a Mode, either scale a recipe or convert between fresh and canned.
- Enter Your Numbers, the amount plus servings, or the amount plus its form.
- Read the Result, then adjust for taste, since tomato products vary in water and thickness.
What Each Result Means
| Result | What It Tells You |
|---|---|
| Scaled amount | Your ingredient adjusted to the new servings |
| Fresh equivalent | Pounds and medium tomatoes to use |
| Canned equivalent | Cans, ounces, and cups of canned |
| Prep note | How to make the swap work in cooking |
Tomato Fresh and Canned Equivalents
Handy cooking equivalents for swapping fresh tomatoes and canned. Fresh should be peeled, and simmered a little to match canned.
| Canned | Fresh, peeled | Cups |
|---|---|---|
| One 14.5 oz can | about 1 lb (3 medium) | about 1.75 cups |
| One 28 oz can | about 2 lb (6 medium) | about 3.5 cups |
| 1 cup canned | about 9 oz (a bit over half a pound) | 1 cup |
| 1 lb fresh | 1 lb (3 medium) | about 1.5 cups chopped |
How Does the Conversion Work?
Scaling is a simple ratio. Fresh-and-canned uses a weight equivalence, where about 1 pound of fresh, peeled tomatoes stands in for a 14.5 ounce can.
Fresh to canned: canned ounces = pounds of fresh x 14.5
Canned to fresh: pounds of fresh = canned ounces divided by 14.5
Medium tomatoes = pounds of fresh x 3
Cups canned = canned ounces divided by 8.3
The 14.5 ounce reference is the common small can size, and roughly 1 pound of fresh, peeled tomatoes fills it. Because fresh tomatoes hold more water, a short simmer thickens the swap.
Worked Example
Say a sauce recipe serves 4 and calls for 2 cups of tomatoes, and you want to serve 6. Multiply 2 by 6 divided by 4, which is 3 cups. To use fresh instead of a 28 ounce can, use about 2 pounds of fresh, peeled tomatoes, roughly 6 medium, and simmer a little longer to thicken.
Factors That Change the Result
- Water content: fresh tomatoes are juicier than canned, so a swap may need extra simmering.
- Product type: whole, diced, crushed, sauce, and paste differ in thickness and concentration.
- Fruit size: the number of tomatoes in a pound changes with variety and size.
- Draining: draining canned tomatoes or seeding fresh ones changes the usable amount.
- Taste: canned tomatoes are picked ripe, so flavor and acidity can differ from out-of-season fresh.
Understanding Your Outputs
| Output | Meaning | Best Used For |
|---|---|---|
| Scaled amount | Adjusted ingredient | Cooking for more or fewer |
| Fresh equivalent | Pounds and count | Buying or picking fresh |
| Canned equivalent | Cans and cups | Shopping for canned |
| Prep note | Cooking tip | Making the swap work |
When to Use It
Use it when doubling or halving a recipe, when a recipe calls for canned but you have a garden glut, or when it calls for fresh out of season and you want to use canned. For pure unit conversions, the measurement converter is the better tool.
Common Mistakes to Avoid
- Not peeling fresh: skins toughen in sauces; peel fresh tomatoes when replacing canned.
- Ignoring extra water: fresh adds liquid, so simmer longer or the dish turns watery.
- Confusing product types: a can of paste is far more concentrated than a can of diced.
- Scaling only the tomatoes: when you scale a recipe, scale every ingredient by the same ratio.
- Forgetting seasoning: taste and adjust salt and acid after scaling or swapping.
Accuracy and Limitations
Scaling math is exact; fresh-and-canned figures are cooking estimates.
What It Calculates Accurately: the serving ratio, and the weight-based fresh and canned equivalents.
What It Does Not Account For: exact water content, product type, draining, or fruit size. Adjust by taste and texture as you cook.
Methodology
Method: a serving ratio for scaling and a weight equivalence for fresh and canned. Inputs Used: mode, amount, unit, servings, or form. Scaling: scaled amount = amount x new servings divided by old servings. Equivalence: about 1 pound of fresh, peeled tomatoes equals a 14.5 ounce can; a 28 ounce can equals about 2 pounds; 1 pound of fresh is about 3 medium tomatoes and about 1.5 cups chopped; 1 cup canned is about 8.3 ounces. Rounding: amounts to one or two decimals. Edge cases: zero or empty inputs prompt for valid numbers. Note: tomato products vary, so adjust by taste.
Sources: National Center for Home Food Preservation – Canning Tomatoes, USDA FoodData Central, The Old Farmer’s Almanac – Tomatoes. Last reviewed: September 24, 2026 · Reviewed by Aiza Anwar.
Frequently Asked Questions
How much fresh tomato equals a can of tomatoes?
About 1 pound of fresh, peeled tomatoes, roughly 3 medium, equals a 14.5 ounce can. A 28 ounce can equals about 2 pounds, or about 6 medium tomatoes.
How do I scale a tomato recipe up or down?
Multiply each ingredient by the new servings divided by the old servings. To take a recipe from 4 to 6 servings, multiply everything by 1.5.
Can I use fresh tomatoes instead of canned?
Yes. Peel the fresh tomatoes, use about 1 pound per 14.5 ounce can, and simmer a little longer since fresh holds more water.
How many cups are in a 28 ounce can of tomatoes?
About 3.5 cups, including the juice. A 14.5 ounce can holds about 1.75 cups.
How many medium tomatoes are in a pound?
About 3 medium tomatoes make a pound, though this varies with size. Small plum tomatoes run higher and large beefsteaks lower.
Do I need to peel fresh tomatoes for sauce?
For a smooth sauce, yes. Skins curl and toughen when cooked. Blanch tomatoes briefly, then slip the skins off before cooking.
How much canned equals a pound of fresh tomatoes?
About a 14.5 ounce can, or a little under 2 cups. Drain the can if your recipe needs less liquid.
Is a cup of chopped tomatoes the same as a cup of canned?
Close, but canned includes juice and is packed denser. For accuracy, convert by weight rather than by cups when you can.
Where can I convert plain tomato weights and cups?
Use the measurement converter for direct weight, cup, and can unit conversions. This tool focuses on scaling recipes and swapping fresh for canned.
Related Tomato Tools
Work Out Tomatoes Needed With the Sauce Calculator
This converter gives general cooking conversions. Tomato products vary in water, thickness, and concentration, so adjust by taste and texture. For home canning, follow a tested recipe. Spotted an error? Tell us here.