To convert cups of tomato sauce into ounces, multiply by 8.6421207: one cup comes to 8.6421207 ounces. Every ingredient has its own figure here, because the units are measuring different things and only the density links them.
Water is the yardstick: 1 mL of it weighs 1 g. Tomato sauce comes in at 1.0356 g per mL, or 103.6% of water, which is why a cup of it is 245 g rather than 236.6 g. Volume and weight only line up for water, and only in metric.
A cup of tomato sauce is 245 g when it is measured the standard way, but how it gets into the cup changes the answer: between about 243.8 g and 247.4 g covers the range from lightly spooned to firmly packed. That 1% spread is larger than most of the adjustments recipes fuss over, and it disappears entirely the moment the ingredient is weighed instead.
One cup of tomato sauce is 8.642 oz. US kitchen scales usually step in eighths of an ounce, which is 3.54 g — around 1.45% of a cup of this ingredient, so the scale is precise enough for a full cup and coarse for a spoonful. That is why recipes mix the two systems: ounces for the bulk, spoons for the small amounts.
The condition this weight assumes: Plain passata or smooth sauce, not paste. Concentrated tomato paste is considerably heavier per cup because most of the water has been driven off, so the two are not interchangeable by volume.
The formula
cups- The amount of tomato sauce you are converting, in cups
8.64212067765- Ounces per cup for tomato sauce, from its density of 1.0356 g/mL
ounces- The equivalent quantity in ounces
How it works, step by step
- Enter the quantity in cups.
- It is multiplied by 8.64212067765, the ounces-per-cup figure for tomato sauce.
- The result appears in ounces, with a second reading in g beneath it.
- Use the measure table if you want a standard recipe quantity rather than a number you type in.
Worked examples
1/3 cup of tomato sauce in ounces
Take 1/3 cup of tomato sauce: 0.333333 × 8.6421207 gives 2.88071 ounces. Doubling the batch takes it to 5.76141 ounces, because the relationship is a straight proportion once the density is known.
3/4 cup of tomato sauce in ounces
A recipe calling for 3/4 cup of tomato sauce needs 6.48159 ounces on the scale. The arithmetic is 0.75 × 8.6421207 = 6.4815905, and halving the recipe halves the weight to 3.2408 ounces.
3 cup of tomato sauce in ounces
Take 3 cup of tomato sauce: 3 × 8.6421207 gives 25.9264 ounces. Doubling the batch takes it to 51.8527 ounces, because the relationship is a straight proportion once the density is known.
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Frequently asked questions
How many ounces are in 1 cup of tomato sauce?
One cup of tomato sauce is 8.6421207 ounces. Half that quantity is 4.32106 ounces and double it is 17.2842 ounces, so the figure scales straight up and down — there is no offset in this conversion, only the factor.
Why is a cup of tomato sauce not 236 g like water?
Because weight per cup depends on what is in the cup. Tomato sauce has a density of 1.0356 g per mL where water has 1.00, so a cup of it weighs 245 g rather than 236.6 g. That is a difference of 8.4 g per cup, and it is the reason a single volume-to-weight factor cannot be applied to every ingredient.
Does how I measure it change the weight?
Barely. Tomato sauce does not compress, so a cup of it is 245 g however it is poured — within about 1%, which is inside the accuracy of a domestic scale. This is the group where measuring by volume is defensible.
Is a fluid ounce of tomato sauce the same as an ounce?
No. A fluid ounce is a volume — one eighth of a US cup, 29.57 mL — and an ounce is a weight. One fluid ounce of tomato sauce weighs 1.08 oz, so the two readings differ by 8.03%. They coincide only for something with the density of water, and then only roughly.
Is this a US cup or a metric cup?
US customary: 236.59 mL, which is the cup every US recipe means. A metric cup is 250 mL, so the same cup of tomato sauce would weigh 258.89 g instead of 245 g — 13.9 g more, or 5.67%. Australian and some European recipes use the metric cup, and the difference is large enough to matter in baking.
Do I need a scale for this, or will measuring cups do?
A scale, if the result matters. Volume measuring carries a spread of about 1% for tomato sauce — roughly 2.45 g on a 245 g cup — while a domestic scale is accurate to a gram or two. For anything where the ratio of ingredients drives the outcome, bread and pastry above all, weigh it.
How many cups of tomato sauce is 16 oz?
16 oz of tomato sauce is 1.8514 cups — 0.115712 cups to one ounce, so 16 × 0.115712 = 1.8514. Going that way is a division by 8.64212, or a multiplication by 0.115712 if you prefer.
Tomato sauce in cups and ounces
| Cups | Ounces | Unrounded |
|---|---|---|
| 1/8 cup | 1.08027 oz | 1.080265085 |
| 1/4 cup | 2.16053 oz | 2.160530169 |
| 1/3 cup | 2.88071 oz | 2.880706893 |
| 1/2 cup | 4.32106 oz | 4.321060339 |
| 2/3 cup | 5.76141 oz | 5.761413785 |
| 3/4 cup | 6.48159 oz | 6.481590508 |
| 1 cup | 8.64212 oz | 8.642120678 |
| 1 1/2 cup | 12.9632 oz | 12.96318102 |
| 2 cup | 17.2842 oz | 17.28424136 |
| 3 cup | 25.9264 oz | 25.92636203 |
| 4 cup | 34.5685 oz | 34.56848271 |
Based on 245 g per cup of tomato sauce. One cup of tomato sauce is 8.6421207 ounces.
| Measure | Grams | Ounces | Millilitres |
|---|---|---|---|
| 1 cup | 245 g | 8.64 oz | 236.6 mL |
| 3/4 cup | 183.8 g | 6.48 oz | 177.4 mL |
| 2/3 cup | 163.3 g | 5.76 oz | 157.7 mL |
| 1/2 cup | 122.5 g | 4.32 oz | 118.3 mL |
| 1/3 cup | 81.67 g | 2.88 oz | 78.86 mL |
| 1/4 cup | 61.25 g | 2.16 oz | 59.15 mL |
| 1 tbsp | 15.31 g | 0.54 oz | 14.79 mL |
| 1 tsp | 5.104 g | 0.18 oz | 4.929 mL |
US customary measures: 1 cup = 236.59 mL, 1 tbsp = 14.79 mL, 1 tsp = 4.93 mL.
| Ingredient | Grams per cup | Ounces per cup | Density (g/mL) |
|---|---|---|---|
| Skim milk | 245 g | 8.642 oz | 1.036 |
| Buttermilk | 245 g | 8.642 oz | 1.036 |
| Plain yogurt | 245 g | 8.642 oz | 1.036 |
| Tomato sauce (this page) | 245 g | 8.642 oz | 1.036 |
| Orange juice | 248 g | 8.748 oz | 1.048 |
| Evaporated milk | 252 g | 8.889 oz | 1.065 |
| Peanut butter | 258 g | 9.101 oz | 1.091 |
Ordered by weight. The spread across this group is why a single generic cups-to-grams factor cannot work.