Oil Volume to Weight Converter
Convert oil volume to weight for cooking oils, petroleum fuels, and more.
Supports ml, liters, fl oz, cups, and gallons.
Includes olive oil, canola, coconut, and 17 oil types.
All oils are lighter than water — that is why they float. While water has a density of exactly 1.000 g/ml (by definition at 4°C), cooking oils range from about 0.88 to 0.93 g/ml. This matters more than most people realize.
Why Oil Density Matters in Cooking: When a recipe calls for “1 cup of olive oil,” most people assume 1 cup weighs about 240g (the weight of 1 cup of water). In reality, 1 cup of olive oil weighs only about 218g — 9% less than water. For casual cooking this difference is irrelevant, but for precision baking or macronutrient tracking, weight accuracy is important because nutrition labels report fat content in grams, not milliliters.
The Density Formula: Mass (g) = Volume (ml) × Density (g/ml)
Volume conversions:
- 1 fluid oz = 29.5735 ml
- 1 US cup = 236.588 ml
- 1 US gallon = 3,785.41 ml
- 1 liter = 1,000 ml
Cooking Oil Density Reference:
| Oil | Density (g/ml) | 1 Cup Weight |
|---|---|---|
| Olive Oil (extra virgin) | 0.911 | ~216 g |
| Canola Oil | 0.914 | ~216 g |
| Coconut Oil (liquid) | 0.904 | ~214 g |
| Sunflower Oil | 0.919 | ~217 g |
| Vegetable Oil (soybean) | 0.920 | ~218 g |
Why Coconut Oil Is Listed Twice: Coconut oil undergoes a phase change at approximately 76°F (24°C). Below this temperature it is a white solid with density ~0.925 g/ml. Above it, the oil melts and becomes liquid at ~0.904 g/ml. When measuring coconut oil, always note whether it is solid or liquid — the weight per cup differs.
Petroleum Context — API Gravity: The petroleum industry does not use density directly. Instead they use API Gravity, a scale developed by the American Petroleum Institute: API = (141.5 / Specific Gravity) − 131.5
Where Specific Gravity is the density relative to water. Higher API = lighter oil.
- Gasoline: API ≈ 60 (SG ≈ 0.737)
- Crude oil: API ≈ 30–40 (SG ≈ 0.825–0.876)
- Heavy crude: API < 22 (SG > 0.922)
- Water: API = 10 (SG = 1.000)
Industrial Shipping Context: Tanker ships and pipeline operators need precise density data because oil is bought and sold by mass (metric tons) but physically measured by volume (cubic meters or barrels). A 1% error in density means a 1% error in the financial transaction. Custody transfer measurements use certified density meters and temperature correction.
Temperature Effect on Density: Oil density decreases as temperature rises — roughly 0.0006 g/ml per °C. At 60°C (140°F), olive oil has a density of about 0.875 g/ml instead of 0.911 g/ml at 20°C. Hot oil poured into a measuring cup and allowed to cool will occupy a slightly smaller volume. For most cooking this effect is negligible.
Worked Example — Baking Precision: A cake recipe calls for 200 ml of olive oil. Weight = 200 × 0.911 = 182.2 g If you assumed water density: 200 × 1.0 = 200g — an error of nearly 18g of fat. In a sensitive pastry or calorie-controlled recipe, this could matter.