Olive oil and vegetable oil can both be useful kitchen staples, but they behave differently in flavour, cost, cooking and storage. This guide compares olive oil vs vegetable oil, explains how to choose the best olive oil for cooking, and gives you a simple way to estimate the cost of each option using the prices and quantities on your own shopping list.
Overview
The most useful choice is rarely a matter of naming one oil the overall winner. It depends on the dish, the heat, the flavour you want and how often you use it. Olive oil is particularly versatile for dressings, vegetables, beans, fish, marinades and Mediterranean-style cooking. Vegetable oil is a broad category that usually refers to a neutral-tasting refined oil or blend, making it practical when you do not want the oil to affect the flavour of a cake, stir-fry or fried food.
Extra virgin olive oil is the least processed main grade of olive oil and has a more noticeable character, ranging from grassy and peppery to soft and fruity. Refined olive oil has a milder flavour and is often chosen for higher-heat cooking or recipes where a pronounced olive note is not wanted. The label matters: “vegetable oil” does not identify one single oil, so check the ingredient list if the source or blend is important to you.
For everyday cooking, either oil can work well when used at an appropriate temperature. The best choice is the one that suits the recipe and helps you cook consistently. An oil that is technically suitable but rarely used is not necessarily better value than one that fits your routine.
Quick comparison
| Use | Olive oil | Vegetable oil |
|---|---|---|
| Salad dressings | Excellent, especially extra virgin olive oil | Works, but usually needs stronger seasoning |
| Roasting | Suitable; choose a flavour that complements the food | Suitable when a neutral taste is preferred |
| Sautéing | Suitable for moderate everyday heat | Suitable for moderate to higher heat, depending on the product |
| Baking | Works well in many cakes, breads and savoury bakes | Useful when a neutral flavour and soft texture are priorities |
| Flavour | May add fruity, bitter or peppery notes | Usually mild or neutral |
| Cost comparison | Compare cost per 100 ml, not bottle price alone | Often priced differently by type, brand and pack size |
How to estimate the better-value option
To compare oils fairly, calculate the cost of the amount actually used rather than comparing the shelf price of two bottles. The basic formula is:
Cost per use = bottle price ÷ bottle volume × recipe quantity used
Use the same unit throughout. If a bottle costs £8 and contains 500 ml, its cost is £0.016 per ml. A recipe using 30 ml would therefore use £0.48 of oil under this illustration.
You can also compare standardised prices:
Cost per 100 ml = bottle price ÷ bottle volume × 100
This is useful when bottles have different sizes. A smaller bottle may look cheaper at the shelf, while a larger bottle may have a lower cost per 100 ml. The calculation only shows financial value, however. If a bottle is used slowly and becomes stale before it is finished, the apparent saving may disappear.
For a weekly meal plan, add the quantities used across recipes:
Weekly oil cost = cost per ml × total ml used during the week
Keep the calculation separate for finishing oil and cooking oil if you buy both. A peppery extra virgin olive oil used in small amounts over finished soup or salad may cost more per serving but contribute more flavour, while a milder oil may be used in larger quantities for roasting or baking.
Inputs and assumptions
A reliable comparison needs more than the price on the front of the bottle. Record these inputs whenever you shop:
- Price: use the price you would actually pay, including any promotion only if you can reasonably use the full bottle before quality declines.
- Volume: note the bottle size in millilitres. Do not compare a 750 ml bottle with a 500 ml bottle by price alone.
- Oil type: distinguish extra virgin olive oil, refined olive oil, rapeseed oil, sunflower oil and vegetable-oil blends. They are not interchangeable in flavour or necessarily in cooking performance.
- Quantity used: measure with a spoon, jug or kitchen scale for a few meals. Pouring freely can make a cost estimate unreliable.
- Purpose: record whether the oil is for frying, roasting, baking, a dressing or finishing. This determines how important flavour is.
- Storage and turnover: estimate how quickly you will finish the bottle. Freshness and good storage are part of value.
Smoke point is useful as a practical guide, but it is not a single permanent score for an entire category. It can vary with the oil’s grade, age and refinement, and with how the pan is used. More importantly, the oil should not be allowed to smoke. Use moderate heat, avoid leaving an empty pan heating and reduce the temperature if the oil begins to haze or smoke. For more detail, see this olive oil smoke point guide.
Extra virgin olive oil is not limited to cold dishes. It can be used for everyday sautéing, roasting and many other applications when the heat is controlled. Its stronger flavour may be an advantage with tomatoes, beans, peppers, aubergine, grains and leafy salads, but less suitable when you want the other ingredients to remain delicate. For a fuller discussion, read can you cook with extra virgin olive oil every day?
Worked examples
Example 1: comparing bottle value
Imagine, purely for illustration, that an olive oil costs £7.50 for 500 ml and a vegetable oil costs £4.20 for 750 ml.
- Olive oil: £7.50 ÷ 500 × 100 = £1.50 per 100 ml.
- Vegetable oil: £4.20 ÷ 750 × 100 = £0.56 per 100 ml.
On price per volume, the vegetable oil is lower in this example. That does not automatically make it the best purchase. If you mainly prepare salads and use 15 ml at a time, you may prefer the flavour of olive oil and use less dressing overall because it needs fewer additional ingredients. The next step is to calculate cost per actual use.
Example 2: cost per recipe
Suppose a tray of roasted vegetables uses 30 ml of oil. Using the illustrative prices above:
- Olive oil: £1.50 per 100 ml × 30 ÷ 100 = £0.45.
- Vegetable oil: £0.56 per 100 ml × 30 ÷ 100 = £0.17.
The difference is £0.28 for that tray. You can now decide whether the olive flavour, ingredient preference and role in your wider Mediterranean meal are worth that difference. If you cook four similar trays each week, multiply the difference by four to see the approximate weekly gap. Replace these example prices with your own figures whenever you shop.
Example 3: choosing by outcome
For a lemon-and-herb dressing, extra virgin olive oil may be the more suitable choice because its flavour is part of the dish. For a delicately flavoured sponge cake, a mild olive oil or neutral vegetable oil may produce the result you prefer. For shallow frying, both can be practical if the pan is not overheated and the oil remains clear rather than smoking. This outcome-based approach is more useful than choosing solely by the lowest price.
When to recalculate
Revisit your comparison when the price, bottle size or recipe changes. Supermarket promotions, different brands and changes in pack size can alter the cost per 100 ml even when the product name stays the same. Recalculate if you move from occasional cooking to regular Mediterranean meal prep, because your total weekly use may change substantially.
Review your choice if the oil is sitting beside the cooker, exposed to heat or light, or taking many months to finish. Store olive oil and other cooking oils tightly closed in a cool, dark cupboard, away from the hob and direct sunlight. Buy a size that matches your turnover rather than assuming the largest bottle is the best value.
Before your next shop, write down the price and volume of each oil, calculate the cost per 100 ml, then estimate the cost of two or three meals you regularly make. Keep extra virgin olive oil for dishes where its flavour adds value, choose a milder option when neutrality matters, and use controlled heat for both. This simple check turns an abstract oil comparison into a practical pantry decision that can be updated whenever your prices or cooking habits change.
