Tomato paste is tomatoes cooked way down, so a big pile of fruit becomes a small, intense amount. Tell the tool how many fresh tomatoes you have, or how much paste you need, and it estimates the other side for both a thick, store-style paste and a softer home-canning paste, since yield depends on how far you cook it down.
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What Your Result Means: paste yield varies a lot with thickness, so you get two figures. The thick estimate matches store-bought paste; the softer estimate matches the tested home-canning recipe, which is cooked less and fills more jars. Your batch will land between them, depending on how far you reduce it.
How Many Tomatoes for Tomato Paste?
About 4 pounds of fresh tomatoes per cup for a thick, store-style paste, or roughly 1.5 to 2 pounds per cup for a softer home-canning paste. Tell the tool your fresh weight, or the paste you need, and it estimates both.
- Pick What You Know, fresh tomatoes or a paste target.
- Enter the Amount, and choose the unit.
- Read the Estimate, paste yield or fresh tomatoes needed.
What Each Result Means
| Result | What It Tells You |
|---|---|
| Paste yield | Cups and jars from your tomatoes |
| Fresh tomatoes | Pounds needed for your target |
| Medium tomatoes | Rough count at about 3 to 4 per pound |
| Citric acid (canning) | Batch acid for the tested half-pint recipe |
Fresh to Paste Yields
Estimated cups of paste. A half-pint jar holds about one cup.
| Fresh Tomatoes | Thick Paste | Softer Home-Canning Paste |
|---|---|---|
| 4 lb | about 1 cup | about 2.4 cups |
| 8 lb | about 2 cups | about 4.9 cups |
| 14 lb | about 3.5 cups | about 8.5 cups (the tested recipe’s 8 to 9 half-pints) |
| 16 lb | about 4 cups (1 quart) | about 9.7 cups |
How Is the Yield Worked Out?
The tool uses two yields. A thick paste takes about 4 pounds of tomatoes per cup; a softer home-canning paste takes about 1.65 pounds per cup, from the tested recipe’s 14 pounds for 8 to 9 half-pints. It converts your amount with each and reports both, plus a rough count of medium tomatoes.
Softer paste cups = fresh pounds / 1.65
Fresh pounds = paste cups x 4 (thick) or x 1.65 (softer)
1 quart = 2 pints = 4 cups = 4 half-pint jars
Medium tomatoes = fresh pounds x 453.6 / 123 (about 3.7)
Citric acid for canning = fresh pounds / 14, in teaspoons, stirred into the sieved pulp
Paste is so concentrated because most of a tomato is water. Fresh tomatoes are about 94.5 percent water and canned paste about 73.5 percent, so a thick paste keeps only around a fifth of the fresh weight, and less once skins, seeds, and trimmings are removed.
Worked Example
Say you picked 16 pounds of paste tomatoes. Cooked to a thick, store-style paste, that is about 4 cups, or 4 half-pint jars. Cooked only to the softer home-canning consistency, the same tomatoes fill about 9 to 10 half-pints. Working backward, 2 cups of thick paste takes about 8 pounds of fresh tomatoes.
Factors That Change the Yield
- Thickness: a stiffer paste reduces more and yields less; a looser one yields more.
- Variety: meaty paste types like Roma have less water and give more paste per pound.
- Seeding and skinning: removing skins and seeds lowers the weight that becomes paste.
- Simmer time: longer cooking means a thicker, smaller, more intense paste.
- Straining: milling out skins and seeds gives a smoother paste with a slightly lower yield.
Understanding Your Outputs
| Output | Meaning | Best Used For |
|---|---|---|
| Paste yield | Cups and jars | Planning storage |
| Fresh tomatoes | Pounds needed | Shopping or picking |
| Medium tomatoes | Rough count | Judging a harvest |
When to Use It
Use it before a paste-making day, or to see how much a recipe’s paste will cost you in fresh tomatoes. Pair it with the canning yield calculator for other products and the sauce calculator for sauce.
Common Mistakes to Avoid
- Underestimating fresh weight: paste takes far more tomatoes than sauce for the same jar.
- Rushing the simmer: paste needs slow, patient reduction to get thick without scorching.
- Not stirring near the end: thick paste catches and burns easily; stir often.
- Skipping or misplacing acid: the tested recipe adds 1 teaspoon of citric acid per 14 pounds of tomatoes to the sieved pulp before cooking down, not to each jar.
- Expecting sauce yields: paste is much more concentrated, so the numbers are very different.
Accuracy and Limitations
Paste yield depends mostly on how far you cook it, so the tool gives a thick and a softer estimate rather than one exact number.
What It Calculates: approximate paste yield or fresh tomatoes needed.
What It Does Not Do: replace a tested recipe. For canning paste, follow the tested NCHFP recipe exactly: half-pint jars only, with the citric acid stirred into the sieved pulp before cooking down.
Methodology
Method: the calculator converts your amount with two yields and reports both. Thick paste: about 4 pounds of tomatoes per cup (16 per quart, the same figure our canning yield tool uses). This follows from water content: fresh tomatoes are about 94.5 percent water and canned paste about 73.5 percent (USDA FoodData Central), so paste keeps roughly a fifth of the fresh weight before losses from skins, seeds, and trimming. Softer paste: about 1.65 pounds per cup, from the National Center for Home Food Preservation recipe of 14 pounds of tomatoes for about 8 to 9 half-pints. Inputs Used: whether you have fresh tomatoes or a paste target, the amount, and the unit. Conversions: 1 quart equals 2 pints equals 4 cups; 1 kilogram equals about 2.2 pounds; medium tomatoes at 123 grams each (USDA FoodData Central), about 3 to 4 per pound; citric acid for canning at 1 teaspoon per 14 pounds, as in the tested recipe. Rounding: pounds and cups to one decimal. Note: a looser paste yields more and a stiffer one less.
Sources: National Center for Home Food Preservation – Tomato Paste, USDA FoodData Central, The Old Farmer’s Almanac – Tomatoes. Last reviewed: September 26, 2026 · Reviewed by Aiza Anwar.
Frequently Asked Questions
How many tomatoes does it take to make tomato paste?
About 4 pounds of fresh tomatoes per cup for a thick, store-style paste, so 16 pounds makes roughly a quart. A softer home-canning paste takes less, about 14 pounds for 8 to 9 half-pints.
How much paste does a bushel of tomatoes make?
A bushel is about 53 pounds, so it yields roughly 13 cups, a little over 3 quarts, of thick paste, or much more of a softer paste, depending on how far you reduce it.
Why does paste need so many tomatoes?
Most of a tomato is water. Making paste means simmering that water off, so a large amount of fruit shrinks to a small, intense paste.
What are the best tomatoes for paste?
Meaty, low-moisture paste types such as Roma, San Marzano, and other plum tomatoes. They have fewer seeds and less juice, so they thicken faster.
How long does it take to cook tomato paste?
Several hours of slow simmering, often three to four or more, depending on your batch size and how thick you want it. Stir often near the end.
Can I can homemade tomato paste?
Yes, but only with the tested NCHFP recipe: 14 pounds of paste tomatoes with 1 teaspoon of citric acid stirred into the sieved pulp before cooking down, packed in half-pint jars. Do not add acid jar by jar, and keep the citric acid to tomato ratio the same if you scale the batch.
How do I store homemade tomato paste?
Refrigerate for up to a week, freeze in small portions or an ice-cube tray for months, or can it with a tested recipe for shelf storage.
Is tomato paste the same as tomato sauce?
No. Paste is cooked much further, so it is far thicker and more concentrated. It takes many more tomatoes per jar than sauce does.
How much fresh tomato equals a can of paste?
A small 6-ounce can holds about 2/3 cup of store-bought paste, which is roughly 2.5 to 3 pounds of fresh tomatoes cooked down.
Related Tomato Tools
Follow the Tested NCHFP Tomato Paste Recipe
This calculator gives estimates for a thick and a softer tomato paste. Real yield depends on your tomatoes and how far you reduce them. For canning paste, follow the tested NCHFP recipe exactly: half-pint jars, with citric acid stirred into the pulp before cooking down, never added jar by jar. Spotted an error? Tell us here.