Common Conversions: 1, 2, 5, 10, and 20 Litres to Kilograms

Whether you are prepping a massive catering order or calculating fuel weight for a road trip, you eventually hit the wall of volume-to-mass conversion. Searching for 5 liter convert to kg or 20 kilos in litres shouldn't require a math degree.

Because different liquids have different densities, 1 kilo in litres of water looks very different from 1 kilo in litres of oil. Below, we break down the most common bulk conversions so you can skip the calculator and just get the answer.

1 Litre to KG (and Vice Versa)

We start with the baseline: how many litres in a kilo? For pure water, the rule is perfectly 1:1. But look at what happens when you introduce cooking oils or dense liquids like milk. For a deeper understanding, read our guide on why volume and mass are different.

• Water: 1 Litre = 1.00 kg | 1 kilo in litres: 1.00 L
• Milk: 1 Litre = 1.03 kg | 1 kilo in litres: 0.97 L
• Cooking Oil: 1 Litre = 0.91 kg | 1 kilo in litres: 1.10 L (See Water vs Oil Density)

2 Litres and 5 Litres in Kilos

This is the sweet spot for home cooks and small commercial kitchens. 2 liter convert to kg is a daily question for baking (read about baking conversions), and 5 litres in kilos usually applies to commercial jugs of cooking oil or large batches of soup.

Notice how honey, which has a density of 1.42 kg/L, gets heavy fast. A 5-litre bucket of honey weighs over 7 kilos!

10 Litres and 15 Litres to KG

When you step up to 10 or 15 litres, the density variations become massive. If you try to guess convert 15 liter to kg assuming it is all water, you could throw off your inventory by several kilograms.

• Water: 10 L = 10 kg | 15 L = 15 kg
• Petrol (Fuel): 10 L = 7.4 kg | 15 L = 11.1 kg
• Diesel: 10 L = 8.35 kg | 15 L = 12.5 kg

If you need to calculate exactly 10 kilos in litres for fuel, simply divide by the density. For petrol (0.74 kg/L): 10 ÷ 0.74 = 13.5 litres.

20 Litres to KG (Bulk and Industrial)

Jerrycans, large chemical buckets, and industrial food supplies are typically sold in 20-litre increments. A common question in workshops is 20 kilos in litres.

graph TD
    A[20 Litre Container] --> B[Water: 20 kg]
    A --> C[Oil: 18.2 kg]
    A --> D[Petrol: 14.8 kg]
    A --> E[Honey: 28.4 kg]

To find 20 kilos in litres for water, it is exactly 20 L. But for an oil (0.91 kg/L), 20 kilograms actually fills up 22 liters of space.

Use the Calculator for Odd Numbers

If your exact number is not on this list—like if you need to know exactly how to convert 1 kg to liter for an obscure chemical, or you have exactly 17.5 liters of something—use the calculator below.

Select your substance, enter your amount, and let the tool do the heavy lifting.