InputsLive
Which way are you converting?
Substitute by volume or weight?
Measuring unit
Butter the recipe calls for
cups
Result
Oil to use
0.75 cups
Swap 1 cups of butter for about 0.75 cups of oil — the ¾ rule.
Oil (cups)0.75
Oil (tbsp)12
Oil (grams)150

Conversions for baking guidance only. Creaming, laminated pastry and frosting may not swap cleanly — see the notes below.

Results are estimates. Consult a professional.

How it's calculated

How the oil to butter conversion works

You cannot swap butter and oil one for one. Butter is about 80% fat, with the rest water and milk solids; baking oils are close to 100% fat. So a recipe needs less oil than the butter it replaces. The common rule of thumb is three parts oil for four parts butter — about three-quarters of a cup of oil for every cup of butter.

This oil to butter conversion calculator runs that math both ways and in three units. Pick a direction — butter to oil, or oil to butter — then choose to substitute by volume or by weight, and it returns the amount in cups, tablespoons and grams, updated live as you type.

oil = butter × 0.75 (by volume — the 3:4 rule)
oil = butter × 0.80 (by weight — butter is ~80% fat)
butter = oil ÷ 0.75 or ÷ 0.80 (the swap, reversed)
Butter sits near 80% fat and oil near 100%, which is why the working ratio is 3 parts oil to 4 parts butter by volume. Gram weights for 1 cup butter (227 g) and 1 cup vegetable oil (200 g) come from the King Arthur Baking Ingredient Weight Chart.
Example

A worked oil to butter conversion example

Example: a cake recipe calls for 1 cup of butter

Priya wants to bake a quick olive-oil cake but the recipe is written for 1 cup of butter. She is mixing the batter by hand, no creaming, so oil will work. She needs to know how much oil to pour in.

Step 1 — Convert by volume (the ¾ rule)

By volume, oil = butter × 0.75. So 1 cup × 0.75 = 0.75 cup of oil. In tablespoons that is 0.75 × 16 = 12 tbsp; in grams, 0.75 cup × 200 g per cup = 150 g.

Step 2 — Check it by weight

If Priya bakes with a scale, the weight method is tighter. One cup of butter weighs 227 g, and oil = butter × 0.80, so 227 × 0.80 = 181.6 g of oil — about 0.91 cup. The two methods differ a little, which is normal; see the section below on which to trust.

Step 3 — Read it off in your unit

Priya is using cups, so she pours ¾ cup of oil in place of the cup of butter. Had the recipe said 1 stick (½ cup) of butter, the same rule gives 6 tablespoons of oil.

1 cup butter → ¾ cup (12 tbsp / 150 g) oil
That is the headline swap by volume. Because oil carries no water, an oil cake bakes denser and stays moist longer than the butter original — a fair trade when you are not creaming.
Quick reference

Oil to butter conversion chart

This chart applies the 3:4 volume rule to the amounts recipes use most. Read left to right to swap butter for oil; read right to left to swap oil for butter. Grams use 227 g per cup of butter and 200 g per cup of oil.

ButterOil (by volume)Oil in tbspOil in grams
1 tsp¾ tsp0.25 tbsp3.1 g
1 tbsp¾ tbsp0.75 tbsp9.4 g
¼ cup (½ stick)3 tbsp3 tbsp37.5 g
½ cup (1 stick)6 tbsp6 tbsp75 g
¾ cup9 tbsp9 tbsp112.5 g
1 cup (2 sticks)¾ cup12 tbsp150 g
1½ cups1⅛ cups18 tbsp225 g
2 cups (4 sticks)1½ cups24 tbsp300 g

All figures use the by-volume 3:4 rule (oil = butter × 0.75). 1 US stick of butter = ½ cup = 8 tbsp. Switch the calculator to "by weight" for a scale-based swap.

Common amounts

How much oil for 1 cup or 1 stick of butter?

These are the two questions cooks ask most mid-recipe, so here they are answered directly.

  • 1 cup of butter → ¾ cup of oil (12 tbsp, or 150 g).
  • 1 stick (½ cup) of butter → 6 tbsp of oil (about 75 g).
  • ½ stick (¼ cup) of butter → 3 tbsp of oil (about 37.5 g).
  • The other way, ½ cup of oil → about ⅔ cup of butter.

If your recipe is in grams, switch the calculator to weight: 1 cup of butter weighs 227 g and converts to 181.6 g of oil. For the reverse trip and other ingredients, the butter converter handles sticks, cups, tablespoons and grams.

Which method

By volume vs by weight: which conversion to use

The two methods give slightly different answers, and that trips people up. By volume the swap is 0.75; by weight it is 0.80. Neither is wrong — they measure butter's fat content from different angles.

Use the volume method (0.75) for everyday baking

If you measure in cups and tablespoons, the 3:4 rule is the practical choice. It is the figure nearly every recipe and conversion chart uses, and it is close enough for cakes, muffins, quick breads and brownies. Three-quarters of a cup of oil per cup of butter, and you are done.

Use the weight method (0.80) when you bake with a scale

Weighing is the more precise way to bake, and by weight oil is 80% of the butter, because butter is roughly 80% fat. For 200 g of butter, use 160 g of oil. The weight swap also sidesteps the small density gap between butter and oil that the volume rule glosses over.

Pick one and stay with it
Don't mix methods inside one recipe. Cups all the way (0.75), or grams all the way (0.80). The calculator's volume/weight toggle keeps you on a single track.
Limits

When you can't swap butter for oil

Most charts stop at the ratio and leave out the part that ruins bakes: butter does jobs oil simply cannot. Where a recipe leans on solid fat, no conversion factor saves it. Three cases matter.

Creaming — when air is the point

Creaming beats softened butter with sugar until it is pale and fluffy, and the sugar crystals cut tiny air pockets into the solid fat. Those pockets are what make a butter cake or a classic cookie rise and turn tender. Oil is liquid, so it cannot trap air this way. Swap oil into a creamed recipe and you get a flatter, denser, more cake-like result.

Laminated pastry — when butter is the structure

Croissants, puff pastry and flaky pie crust depend on cold, solid sheets of butter that steam apart into layers in the oven. Oil stays liquid and coats the flour evenly, so it produces a short, crumbly texture with no flake at all. Here butter is not flavour, it is architecture, and oil cannot stand in.

Frosting and anything that sets firm

Buttercream, shortbread and frostings hold their shape because butter is firm at room temperature. Oil never sets, so an oil frosting slumps and an oil shortbread spreads into a greasy puddle. The reliable swap is oil into batters that are already pourable. For temperature-sensitive bakes, our oven temperature converter helps you dial the heat in too.

Pourable batter? Oil is fine. Solid fat doing a job? Keep the butter.
Quick breads, muffins, snacking cakes and brownies swap beautifully. Creamed cookies, laminated pastry, frosting and shortbread do not.
Choosing oil

Which oil to use in place of butter

The conversion ratio is the same for any liquid oil, but flavour is not. The oil you choose either disappears into the bake or becomes part of it.

OilFlavourBest for
Vegetable / canolaNeutralWhen you want no oil taste — most cakes, muffins, brownies
Light olive oilMild, cleanEveryday baking where you want oil's moisture, not its flavour
Extra-virgin olive oilFruity, pepperyOlive-oil cakes, citrus and chocolate bakes that can carry it
Melted coconut oilFaint coconutA near-butter swap; see the 1:1 note below
Avocado oilVery mildA high-heat, neutral alternative to vegetable oil

A good rule from olive-oil bakers: only bake with an oil you would happily eat on a salad. For chocolate or citrus, a medium or robust extra-virgin oil stands up; for delicate crumbs, choose a milder one.

Oil-selection guidance follows California Olive Ranch's recipe-makeover advice on swapping olive oil for butter, and the principle that good olive oil adds flavour and keeps baked goods moist.
Recipe tweaks

Adjusting liquid and texture after the swap

Removing butter removes its water, and that small change shows up in the dough. A couple of easy adjustments close the gap.

  • Add a little liquid to dry doughs. Butter is about 20% water; oil is none. For drier batters and doughs, add 1–2 tablespoons of milk or water per cup of butter you replaced.
  • Expect a moister, denser crumb. Oil coats flour proteins more thoroughly, so the bake stays soft for longer but rises a touch less. This is a feature in snacking cakes and muffins.
  • Don't over-mix. Without creaming, you only need to combine until smooth; beating an oil batter hard does nothing useful and can toughen it.
  • Mind the browning. Butter's milk solids brown and add flavour. Oil does not, so an oil bake can look paler — a minute or two longer, or a slightly hotter oven, helps.

For swaps beyond fat — flour, sugar, liquids by volume or weight — reach for the cooking converter, which bridges cups and grams for any ingredient.

The exception

Coconut oil and the 1:1 exception

Coconut oil breaks the rule. It is solid at room temperature, so it behaves more like butter than like liquid oil — and it can be creamed and can set firm. For coconut oil, swap one for one with butter rather than using the ¾ factor.

Two cautions. Coconut oil carries a faint coconut flavour, mild in refined oil and stronger in virgin, so it suits some bakes more than others. And it is high in saturated fat, so it is not the heart-healthier swap that liquid oils are.

Mayo Clinic notes that liquid plant oils such as olive and canola carry healthier unsaturated fats than butter's saturated fat, and recommends baking with oil where the recipe allows.
Definitions

Oil to butter conversion definitions

The standard by-volume swap: three parts oil for four parts butter, or oil = butter × 0.75. Three-quarters of a cup of oil replaces a cup of butter.
Butter is roughly 80% fat and 20% water plus milk solids. That 80% is why the weight swap uses 0.80, and the water is why oil bakes drier-acting unless you add a little liquid.
Beating solid butter with sugar to whip air into the fat. The trapped air leavens butter cakes and cookies. Oil is liquid and cannot be creamed, so it cannot replace butter in recipes that rely on this step.
Folding cold butter into dough in thin sheets so it steams into flaky layers — the basis of croissants and puff pastry. Oil cannot laminate, so it cannot make a flaky pastry.
The US unit: 1 stick = ½ cup = 8 tablespoons = 113 g. By the 3:4 rule, one stick of butter becomes 6 tablespoons of oil.
Accuracy

How accurate is this oil to butter calculator?

The arithmetic is exact. By volume it applies 0.75 and by weight 0.80, using 227 g per cup of butter and 200 g per cup of oil from the King Arthur weight chart. Enter your amount and the cups, tablespoons and grams are right to the decimal.

What the calculator can't judge is whether oil belongs in your recipe at all. The ratio is reliable for pourable batters — cakes, muffins, quick breads, brownies. It cannot rescue a creamed cookie, a laminated pastry or a frosting, where butter's solid structure does the work. Treat the numbers as an exact fat swap, and the technique notes above as the guard rails on when to use it.

Questions

Frequently asked questions about the free Oil to Butter Conversion calculator

An oil to Butter Conversion calculator is a free online tool that helps you swap butter for oil or oil for butter in baking — both directions, in cups, tablespoons and grams, by volume or weight. Butter is about 80% fat and 20% water; oil is nearly 100% fat, so a recipe needs less oil than the butter it replaces. It runs entirely in your browser with instant results and no sign-up.
Use ¾ cup of oil for 1 cup of butter — that's 12 tablespoons, or about 150 g. The rule is 3 parts oil to 4 parts butter, because butter is roughly 80% fat and oil is nearly 100% fat, so you need less of it.
One stick of butter (½ cup, 8 tablespoons) becomes 6 tablespoons of oil — about 75 g. Halve it for a half-stick: ¼ cup of butter swaps to 3 tablespoons of oil.
By volume, use 0.75 (¾ cup oil per cup butter) — the practical choice for cups and tablespoons. If you bake with a scale, use 0.80 by weight (200 g butter → 160 g oil), which is a touch more precise. Pick one method and stay with it through the whole recipe.
No. Oil works in pourable batters like cakes, muffins, quick breads and brownies. It can't replace butter where solid fat does a job — creaming (cookies and butter cakes), laminated pastry (croissants, flaky pie crust) or frosting and shortbread, which need butter to set firm.
Yes. Coconut oil is solid at room temperature and behaves like butter, so swap it one for one rather than using the ¾ rule. Note it carries a faint coconut flavour and is high in saturated fat, so it isn't the heart-healthier option that liquid oils like olive or canola are.
About

About this Oil to Butter Conversion calculator

This oil to butter conversion calculator runs entirely in your browser. Nothing you type is sent anywhere — enter a butter or oil amount, pick a direction and a method, and the cups, tablespoons and grams update instantly on your device.

It is part of our cooking and baking calculators, alongside the full library of free calculators for everyday measuring, money and home projects.

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