Butter to Oil Conversion Calculator
Butter is about 81 percent fat and 16 percent water, so a cup of butter does not swap to a full cup of oil. This calculator matches the fat mass of the butter with the fat mass of canola, soybean vegetable, olive or sunflower oil, in either direction, and it shows the water and sodium that the swap removes or adds. All gram weights and nutrition values come from USDA FoodData Central records, fetched November 9, 2026.
Convert
·
Show the math
| Step | Item | Working |
|---|
Why 1 cup of butter is not 1 cup of oil
Butter carries fat, water, milk solids and a little salt. USDA FoodData Central record FDC 173410 (butter, salted) gives 81.1 g fat and 16.2 g water per 100 g of butter. Cooking oils are essentially all fat. FDC 171413 gives 100 g fat per 100 g of olive oil. If you replace 1 cup of butter with 1 cup of oil, the recipe gets about 32 g more fat with olive oil (216 − 184.10) and about 34 g more fat with the 218 g oils (218 − 184.10). It also loses the 36.77 g of water that the butter held.
The fat-mass match in this calculator uses the published FDC gram weights for each volume unit. It keeps the fat the same and changes everything else. A kitchen scale gives the most exact result.
The gram weights this calculator uses
| Food | g per tsp | g per tbsp | g per stick | g per cup | Fat per 100 g | Sodium per 100 g |
|---|---|---|---|---|---|---|
| Butter, salted | 4.7 (calculated) | 14.2 | 113 | 227 | 81.1 | 643 mg |
| Butter, without salt | 4.7 (calculated) | 14.2 | 113 | 227 | 81.1 | 11 mg |
| Canola oil | 4.5 | 14.0 | n/a | 218 | 100 | 0 mg |
| Soybean vegetable oil, refined | 4.5 | 13.6 | n/a | 218 | 100 | 0 mg |
| Olive oil, salad or cooking | 4.5 | 13.5 | n/a | 216 | 100 | 2 mg |
| Sunflower oil, linoleic | 4.5 | 13.6 | n/a | 218 | 100 | 0 mg |
FDC gives no teaspoon weight for butter as a portion weight, so this page uses the FDC portion weights that the records list (1 tbsp, 1 stick and 1 cup for butter). The butter teaspoon value in the calculator is the tablespoon value divided by 3, and the table marks it as calculated. FDC gives different tablespoon weights for the four oils (13.5 to 14.0 g). This page uses each record’s own value and does not mix them.
Swap tables by fat mass
If a recipe calls for 1 unit of the food in the left column, use this much of the food across the top. Values are rounded to 3 decimals for display.
| Recipe calls for 1… | Soybean oil | Olive oil | Canola oil | Sunflower oil |
|---|---|---|---|---|
| cup butter | 0.844 cup | 0.852 cup | 0.844 cup | 0.844 cup |
| stick butter | 0.420 cup | 0.424 cup | 0.420 cup | 0.420 cup |
| tbsp butter | 0.847 tbsp | 0.853 tbsp | 0.823 tbsp | 0.847 tbsp |
These ratios disagree with the fixed row on the home page substitution tool, which says to use 3/4 of a cup of olive oil for 1 cup of butter. The fat-mass result for olive oil is 0.852 cup per cup of butter. A 3/4 cup swap is 162 g of olive oil (216 × 0.75), which is about 22 g less fat than the 184.10 g in the butter. This page shows both figures and its math so that you can pick. The 3/4 figure on the home page has no cited source.
What the swap removes
Replacing butter with oil removes the water, the milk solids and most of the sodium. For 1 cup of salted butter (227 g) the swap removes 36.77 g of water (227 × 16.2 / 100) and 1459.6 mg of sodium (227 × 643 / 100). For unsalted butter the sodium removed is 25.0 mg per cup (227 × 11 / 100). The calculator shows both values for the amount you enter. It subtracts the sodium of the oil, which matters only for olive oil (2 mg per 100 g). For 1 cup of salted butter and olive oil the net value is 1455.9 mg.
This page gives arithmetic only. It does not test baking results and it does not claim that a swap bakes the same. Oil replaces the fat of the butter, but not its water or milk solids, so a batter or dough can behave differently. Test a small batch when the result matters.
How to use the calculator
Pick the direction. Type the amount from the recipe and select its unit (cups, sticks, tablespoons, teaspoons or grams). Pick the oil. The converter gives the same fat mass of the other food, the grams of fat shared by both amounts, and the water and sodium that the swap removes (butter to oil) or adds (oil to butter).
By weight. If you have a kitchen scale, select grams. The gram path is the most direct because it needs no portion weight.
Frequently asked questions
- How much olive oil equals 1 cup of butter?
- About 0.852 cup, a little over 3/4 cup plus 1 tablespoon and a half. 1 cup of butter is 227 g (FDC 173410). Its fat is 227 × 81.1 / 100 = 184.10 g. A cup of olive oil is 216 g (FDC 171413). 184.10 / 216 = 0.852 cup.
- How much oil equals 1 stick of butter?
- A stick is 113 g of butter (FDC 173410) with 91.64 g of fat. That fat is 0.420 cup of soybean, canola or sunflower oil (91.64 / 218) or 0.424 cup of olive oil (91.64 / 216), which is about 6 and 3/4 tablespoons of olive oil (91.64 / 13.5 = 6.79).
- How much butter equals 1 cup of oil?
- For olive oil, 1 cup of butter holds 184.10 g of fat and 1 cup of olive oil holds 216 g of fat, so you need 216 / 184.10 = 1.173 cups of butter to match the fat of 1 cup of olive oil. For the 218 g oils the number is 1.184 cups.
- Can I use the 3/4 cup rule instead?
- The home page substitution tool gives 3/4 cup of olive oil for 1 cup of butter. The fat-mass result from the FDC values is 0.852 cup. The 3/4 cup swap gives about 22 g less fat (184.10 − 162). This page shows both figures and its math. It does not present the 3/4 rule as a sourced fact because the home page row cites no source.
- Does the swap change the sodium?
- Yes. FDC 173410 gives 643 mg sodium per 100 g of salted butter. 1 cup removes 1459.6 mg of sodium. Unsalted butter (FDC 173430) has 11 mg per 100 g, so 1 cup removes 25.0 mg. Oils carry 0 to 2 mg per 100 g.
Method and sources
Gram weights, fat, water and sodium values were taken from USDA FoodData Central records fetched November 9, 2026.
- Butter, salted. USDA FoodData Central record FDC 173410 (SR Legacy, 4/1/2019). Fat 81.1 g, water 16.2 g, sodium 643 mg per 100 g. Portion weights 1 tbsp 14.2 g, 1 stick 113 g, 1 cup 227 g. USDA FoodData Central
- Butter, without salt. FDC 173430. Fat 81.1 g, water 16.2 g, sodium 11 mg per 100 g, same portion weights. USDA FoodData Central
- Canola oil. FDC 172336. Fat 100 g per 100 g. Portion weights 1 tsp 4.5 g, 1 tbsp 14.0 g, 1 cup 218 g. USDA FoodData Central
- Soybean vegetable oil, refined. FDC 172370. Fat 100 g per 100 g. 1 tsp 4.5 g, 1 tbsp 13.6 g, 1 cup 218 g. USDA FoodData Central
- Olive oil, salad or cooking. FDC 171413. Fat 100 g per 100 g, sodium 2 mg per 100 g. 1 tsp 4.5 g, 1 tbsp 13.5 g, 1 cup 216 g. USDA FoodData Central
- Sunflower oil, linoleic (approx. 65%). FDC 171025. Fat 100 g per 100 g. 1 tsp 4.5 g, 1 tbsp 13.6 g, 1 cup 218 g. USDA FoodData Central
- Volume units. NIST Special Publication 811, Appendix B.8 (its mL factors give 1 tbsp = 3 tsp and 1 cup = 48 tsp). nist.gov
Derived figures. Conversions use published average densities from the portion weights above. The butter teaspoon weight is the FDC tablespoon weight divided by 3. All arithmetic runs client-side in this page. Results in grams are rounded to whole grams for display. The Show the math table gives gram values to 2 decimals. Nutrition estimates use USDA reference data and do not replace professional dietary advice.
Conversions use published average ingredient densities. Brand, humidity, and how you fill the cup all move the real weight, so weigh on a scale when a recipe has to be exact. Consult a dietitian for medical advice.
IngredientCalculator is an independent project by Michael, a developer who is not a baker or a dietitian. The site turns published reference data into free calculators.