Substitute Diced Tomatoes for Tomato Paste: The Easy Method

Yes, you can substitute diced tomatoes for tomato paste, but they need draining and usually simmering first: diced tomatoes contain much more water and have a fresher, less concentrated flavor. This simple reduction makes a thick tomato concentrate for sauces, soups, stews, and braises, or you can use drained tomatoes directly when a little extra liquid will not matter.

Ingredients

1 cup (240 ml; about 170 g) canned diced tomatoes, thoroughly drained

This one-ingredient batch makes about ¼ cup (60 ml) of thickened tomato, enough to stand in for approximately 2 tablespoons of tomato paste in most cooked recipes. The final yield varies with the brand, how thoroughly the tomatoes are drained, and how much liquid evaporates. No oil, salt, or seasonings are required, so the result can go into recipes without adding an unexpected flavor.

Instructions

Drain the tomatoes. Set a fine-mesh strainer over a bowl and pour in the diced tomatoes. Let them drain for 5 minutes, then gently press them with the back of a spoon to remove loose liquid. Do not crush them hard enough to force all the pulp through the strainer. If the tomatoes are packed in thick purée rather than juice, drain them briefly and keep the purée to add back a little at a time if needed.
Check the amount and texture. Measure 1 cup (240 ml; about 170 g) of drained tomatoes. For the smoothest result, chop large pieces with a knife or pulse them once or twice in a food processor. Do not blend them into a thin liquid; a little texture is fine because the tomatoes will soften as they cook.
Start reducing. Put the tomatoes in a small, wide saucepan over medium heat. When they begin to bubble, lower the heat to medium-low so they simmer gently. Stir and scrape the bottom every few minutes. A wide pan helps water evaporate faster, while a small, deep pan is more likely to make this step take longer.
Cook until thick. Simmer for 20 to 24 minutes, stirring more often as the mixture gets thicker. The tomato should reduce to roughly ¼ cup (60 ml), look glossy and concentrated, and leave a track for a moment when a spoon is drawn across the pan. If it is still loose or watery, continue simmering in 2-minute increments rather than relying only on the clock.
Use or cool. Stir the thickened tomatoes into your recipe where the tomato paste would normally go. If using them later, transfer them to a clean, shallow container and cool promptly. This small batch is meant as a cooking ingredient, not a ready-to-eat sauce; taste and season the finished dish as its recipe directs.

For the best match, use this reduced batch in place of about 2 tablespoons of tomato paste. If you need a different amount, scale the tomatoes and the reduction: for each 1 tablespoon of paste, start with about ½ cup (120 ml; 85 g) of well-drained diced tomatoes and simmer until thick. Since pan width and tomato brands affect evaporation, judge the consistency as well as the volume.

Tips

Drain before measuring. The liquid in a can is the main reason this swap can thin out a recipe. Drain the tomatoes first, especially if you plan to add them straight to a soup, stew, or sauce. Save the drained juice in the refrigerator and use a little elsewhere in the dish if it suits the recipe, rather than pouring it all back into the substitute.
Account for the extra moisture. If you skip the reduction, use about 2 to 3 tablespoons of well-drained diced tomatoes for each tablespoon of paste, then reduce another liquid in the recipe by roughly the same amount if practical. This quick option is less concentrated and may leave visible tomato pieces, so it is better in chunky dishes than in a smooth, tightly balanced sauce.
Cook it down; don’t just mash it. Crushing diced tomatoes makes smaller pieces, but it does not remove water or reproduce paste’s concentrated flavor. Give the mixture time to simmer, and let it thicken until it clings to a spoon. Adding extra raw tomatoes to compensate for a weak tomato flavor often makes a dish more watery instead.
Adjust seasoning at the end. Canned tomatoes differ in salt level and acidity, and the main recipe may already include salt, stock, wine, or other acidic ingredients. Keep this substitute plain, taste the whole dish after it cooks, and then adjust seasoning. If the finished dish tastes sharper than expected, a small pinch of sugar can soften the impression, but it is not necessary in every recipe.

Serving Suggestions

This concentrate is designed to be stirred into another cooked dish, not served as a standalone condiment. Add it where the recipe calls for tomato paste: often after aromatics have softened and before broth, water, or other liquids go into the pot. Let it cook with the other ingredients so its tomato flavor has time to blend into the dish.

It works particularly well in chili, lentil soup, vegetable stew, meat sauce, curry, braised beans, and pan sauces. In a recipe that browns tomato paste in oil for a minute or two, add the reduced tomatoes and cook them briefly with the aromatics before adding liquid. They may splatter, so lower the heat and stir carefully. For smooth recipes such as a silky soup or finely textured pasta sauce, blend the finished dish if needed rather than expecting every brand of diced tomatoes to disappear completely.

Variations

Use fresh tomatoes: Peel and chop ripe tomatoes, then drain and reduce them in the same way. Fresh tomatoes vary in water content, so allow extra simmering time if they are especially juicy. Their flavor is usually brighter and less consistently concentrated than canned tomatoes.
Make a smoother substitute: Crush the drained tomatoes with a fork or pulse them briefly before simmering. This helps the mixture become more uniform without adding any extra liquid. A blender can make it too foamy or thin if run for a long time, so use short pulses.
Use fire-roasted diced tomatoes: Drain and reduce them as directed for a gentle smoky note. This can suit chili, beans, and hearty stews, but it will change the flavor, so choose plain diced tomatoes when the finished dish needs a neutral tomato base.
Skip the pan when the recipe is forgiving: In a long-simmered soup or stew, add well-drained diced tomatoes directly and let the dish cook uncovered for a while to evaporate excess moisture. This is convenient, but the result is less concentrated and the recipe may need a longer reduction. It is not the best choice for a quick sauce or a recipe with carefully measured liquid.

Storage and Reheating

Use the reduced tomatoes immediately, or refrigerate them in a covered container within 2 hours of cooking. They keep for 3 to 4 days in the refrigerator. Because the batch is small, a shallow container helps it cool promptly; do not leave it at room temperature while you finish other tasks. Label the container with the date if you are storing it alongside other prepared ingredients.

To reheat the substitute by itself, warm it in a small saucepan over low heat, stirring until hot. Add a teaspoon of water only if it has become too stiff to stir; the goal is still a thick mixture. You can also stir the cold concentrate directly into a dish that will be cooked through. If you have mixed it into a larger batch of leftovers, reheat those leftovers to 165°F (74°C), stirring where possible so they heat evenly. Freeze extra concentrate in a small, freezer-safe container for up to 2 to 3 months for best quality; thaw it in the refrigerator and use it in a cooked dish.

Frequently Asked Questions

What is the ratio of diced tomatoes to tomato paste?
For a close substitute, start with about ½ cup (120 ml; 85 g) of well-drained diced tomatoes for every 1 tablespoon of tomato paste, then simmer until the tomatoes are thick and reduced to around 1 tablespoon. For this recipe’s batch, 1 cup of drained tomatoes reduces to about ¼ cup and replaces approximately 2 tablespoons of paste. Exact yield depends on the tomatoes and pan, so thickness matters more than a precise final measure.

Can I put diced tomatoes straight into a recipe instead of tomato paste?
Often, yes, particularly in a soup, chili, or stew with enough time to simmer. Drain them and use about 2 to 3 tablespoons per tablespoon of paste, while accounting for the moisture they bring. The dish will have a lighter tomato flavor and may contain tomato pieces. For a quick-cooking recipe or a thick sauce, reducing the tomatoes first gives a more dependable result.

Will the finished dish taste the same?
Not exactly. Tomato paste is cooked down to a highly concentrated, smooth ingredient, while diced tomatoes are juicier and usually taste fresher. Reducing them narrows the difference and makes the flavor more suitable for cooked dishes, but it may still be milder or slightly brighter. A long simmer and good seasoning help the tomato flavor blend in.

Can I use tomato purée or crushed tomatoes instead?
Yes. Tomato purée is usually smoother than diced tomatoes and may need less chopping, but it still needs simmering to become thick enough to replace paste. Crushed tomatoes also work; drain them if they are watery and reduce them until they leave a brief track when stirred. Since products vary in thickness, add less liquid to the main recipe at first and adjust as it cooks.

What if my substitute is too watery?
Keep simmering it uncovered over medium-low heat, stirring regularly and scraping the pan so it does not stick. If the tomatoes are already in the main dish, simmer that dish uncovered when its ingredients allow, or remove a little liquid with a ladle. Avoid correcting watery tomatoes by adding more raw diced tomatoes; that adds still more moisture.

Can I make this substitute ahead?
Yes. Cook it until thick, cool it promptly, and refrigerate it in a covered container for 3 to 4 days, or freeze it for 2 to 3 months for best quality. Thaw frozen portions in the refrigerator. Keep the mixture plain until you add it to a recipe, since seasoning it in advance can make it harder to balance the finished dish.

More recipes to cook

Safety notes: safe minimum internal temperatures from USDA FSIS; raw and undercooked fish guidance from the U.S. FDA. Food safety notes

Spotted an error? Tell us and we will correct it (corrections policy).