Oil to Butter Converter

Convert between oil and butter for any baking or cooking recipe. Butter contains about 80% fat and 20% water and milk solids, while oil is 100% fat — so the conversion is not a simple 1:1 swap. This calculator also shows margarine, coconut oil, and applesauce equivalents for healthier substitutions. See also our Cooking Converter and Cups to Grams Converter.

How to Convert Oil to Butter

The key to converting between oil and butter is understanding their fat content difference. Butter is approximately 80% fat and 20% water and milk solids. Oil is 100% fat. Because butter contains less fat per unit volume, you need more butter to match the fat content of oil. The standard conversion ratio is 1.2 — meaning you need 20% more butter than oil.

1. Determine the amount of oil (or butter) in your recipe
2. To convert oil to butter: multiply by 1.2
3. To convert butter to oil: multiply by 0.8 (or divide by 1.2)
4. Adjust for texture preferences — butter adds flavor and structure that oil does not

Why the Conversion Is Not 1:1

Many people assume you can swap oil and butter in equal amounts, but this leads to incorrect results. Butter is only 80% fat — the remaining 20% is water and milk solids. When you melt butter, you can see this separation: the clear yellow liquid is butterfat, and the white residue is milk solids and water.

Because oil is 100% fat, using the same volume of butter would give you 20% less fat in your recipe. This can make baked goods drier and less tender. The 1.2 multiplier compensates for this difference, ensuring the total fat content remains the same. However, the extra water in butter also affects recipes — it creates steam during baking, which can help with leavening in pastries and pie crusts.

Worked Example: Converting a Cake Recipe

A cake recipe calls for ¾ cup of vegetable oil and you want to use butter instead. Multiply 0.75 × 1.2 = 0.9 cups of butter. Since 0.9 cups is awkward to measure, that is approximately ¾ cup + 2½ tablespoons of butter (14.4 tablespoons total). Melt the butter before adding it to match the liquid consistency of oil in the batter. The cake will have a richer, more buttery flavor but a slightly different crumb texture.

Oil to Butter Reference Table

Fat Substitutes for Baking

Beyond the oil-butter swap, there are several other fat substitutes commonly used in baking:

• Margarine: Can replace butter 1:1 in most recipes. Choose stick margarine (not tub) for baking as it has similar fat content to butter
• Coconut oil: Replaces other oils 1:1 by volume. Solid at room temperature, so melt it first for liquid oil substitution. Adds subtle coconut flavor
• Applesauce: Can replace 50-75% of oil in baking for lower-calorie results. Use unsweetened applesauce and reduce sugar slightly. Best in muffins, quick breads, and cakes
• Greek yogurt: Can replace half the butter in recipes. Adds moisture and protein while reducing fat
• Avocado: Replaces butter 1:1 in brownies and chocolate baked goods. Adds healthy fats and creamy texture
• Ghee (clarified butter): Pure butterfat with water and milk solids removed. Replaces oil 1:1 and butter at 0.8:1 ratio

When to Use Oil vs Butter

The choice between oil and butter affects more than just fat content — it changes the texture, flavor, and shelf life of your baked goods:

• Use oil for: Moist cakes, muffins, quick breads, salad dressings, and recipes where you want a tender crumb that stays moist for days
• Use butter for: Cookies (for spread and crisp edges), pie crusts (for flakiness), croissants, and recipes where butter flavor is essential
• Texture difference: Oil produces softer, moister baked goods; butter produces firmer, more structured results with better browning
• Shelf life: Oil-based baked goods stay moist longer; butter-based goods can dry out faster but have better initial texture

Calorie Comparison

Oil has more calories per tablespoon (120 calories) than butter (102 calories) because oil is 100% fat while butter is only 80% fat. However, since you use less oil than butter in a recipe (due to the 0.8 conversion factor), the total calories in the finished dish are similar. One cup of oil has 1,920 calories, while the equivalent 1.2 cups of butter has about 1,958 calories — nearly identical total fat contribution to the recipe.

Frequently Asked Questions