There are 0.454 kg in a pound. That is the answer, usually rounded: 1 avoirdupois pound equals 0.45359237 kilograms, which is 453.6 grams, or 16 ounces. If a recipe calls for 2 pounds of flour, you need 0.907 kilograms. If your scale reads kilograms and the recipe is written in pounds, multiply the pounds by 0.454. This page gives you the table, real cooking examples, and the rounding rules, because 0.454 is close enough for cooking but not exact, and knowing when the difference matters is the skill.
The conversion table
| Pounds | Kilograms | Grams | Ounces |
|---|---|---|---|
| 1/4 lb | 0.113 kg | 113.4 g | 4 oz |
| 1/2 lb | 0.227 kg | 226.8 g | 8 oz |
| 3/4 lb | 0.340 kg | 340.2 g | 12 oz |
| 1 lb | 0.454 kg | 453.6 g | 16 oz |
| 1 1/2 lb | 0.680 kg | 680.4 g | 24 oz |
| 2 lb | 0.907 kg | 907.2 g | 32 oz |
| 3 lb | 1.361 kg | 1,360.8 g | 48 oz |
| 5 lb | 2.268 kg | 2,268.0 g | 80 oz |
| 10 lb | 4.536 kg | 4,535.9 g | 160 oz |
The kilogram figures are rounded to three decimal places. The gram column is the exact equivalent, because a pound is defined as 453.59237 grams.
Worked example 1: a bag of flour and a recipe in kilograms
You have a 5-pound bag of flour, and a European recipe calls for 2 kilograms. Two kilograms is 4.41 pounds, so you need most of the bag — 4.41 pounds out of 5 — and you will have about half a pound left. If the recipe calls for 2.27 kilograms, that is exactly 5 pounds, so you can use the whole bag. The conversion matters most when you are buying in pounds and cooking in kilograms, and the anchor to remember is that a pound is 0.454 kilograms, which is just under half a kilogram.
Worked example 2: a roast that needs weighing in kilograms
An American recipe calls for a 3-pound roast, and you are buying meat in a shop that sells by the kilogram. Three pounds times 0.454 is 1.36 kilograms, so look for a joint labelled 1.3 to 1.4 kilograms. If the joint is 1.5 kilograms, that is 3.3 pounds, and you should add about 10 minutes to the cooking time. The weight matters because the cooking time is calculated from it, and the pound-to-kilogram conversion is the bridge between the recipe and the shop label.
Worked example 3: a large batch, scaled in kilograms
You are making jam and the recipe calls for 5 pounds of fruit, but your scale reads kilograms. Five pounds times 0.454 is 2.27 kilograms, which is 2,268 grams, and you will need a pot that holds at least 4 litres. Working in kilograms makes the maths easy once you have the conversion: 2.27 kilograms of fruit and 2.27 kilograms of sugar is a 1-to-1 ratio, which is obvious in kilograms and less obvious in pounds, where 5 plus 5 is 10. That is why large-batch cooking is easier in metric units, even when the recipe was written in pounds.
Method and source
An avoirdupois pound is defined as exactly 453.59237 grams, and a kilogram is defined as 1,000 grams, so 453.59237 divided by 1,000 is 0.45359237, usually rounded to 0.454. The figure 0.454 is close enough for cooking: the error is 0.1 percent, which is less than half a gram in a pound, and it will not change a recipe. For a precise bake or a large batch, use 0.4536, because the error grows with the amount — 10 pounds times 0.454 is 4.54 kilograms, but 10 pounds is really 4.5359 kilograms, and the difference is 4 grams, which can matter in a precise recipe. In practice, most people use 0.45, which is close enough for shopping but not for baking.
Practical guidance
Buy a kitchen scale that reads grams, and use it for every recipe that gives a weight. Weighing is more accurate than measuring by volume, because a cup of flour can weigh anywhere from 120 to 142 grams depending on how you scoop it, while 454 grams is always 454 grams. When you convert pounds to kilograms, multiply by 0.454 and round the answer to the nearest 10 grams — do not round the conversion factor first. Remember the anchor numbers: a quarter pound is 0.113 kilograms, half a pound is 0.227 kilograms, three quarters is 0.340 kilograms, and a pound is 0.454 kilograms. And if your scale has a grams mode, use it, because grams are more precise than kilograms for amounts under a kilogram.
Frequently asked questions
How many kilograms are in 1 pound?
There are 0.454 kg in 1 avoirdupois pound, usually rounded, and 0.4536 kg exactly. A pound is also 453.6 grams and 16 ounces. Use 0.454 for cooking and 0.4536 for a precise bake.
How many kilograms are in half a pound?
There are 0.227 kg in half a pound. Half a pound is also 226.8 grams and 8 ounces. It is a common amount for butter, cheese, and chocolate in baking.
How many kilograms are in 2 pounds?
There are 0.907 kg in 2 pounds. Two pounds is also 907.2 grams and 32 ounces. It is a common amount for a roast or a large batch of dough.
How many pounds are in 0.454 kilograms?
There is 1 pound in 0.4536 kilograms. Zero point four five four kilograms is the rounded figure for a pound, so if a recipe gives an amount in kilograms that adds up to 0.454, you can weigh it as a pound instead.
How many kilograms are in a pound of butter?
There are 0.454 kg in a pound of butter, the same as in a pound of anything else. A pound of butter is 4 sticks, which is 2 cups, and it weighs 454 grams, which is just under half a kilogram.
Is a pound the same everywhere?
Almost. An avoirdupois pound is 453.6 grams everywhere it is used, by international agreement. The troy pound is different, at 373.2 grams, but it is used only for precious metals. If a recipe says "pound", it means an avoirdupois pound.
The 0.454 rule and when it breaks
Most cooks remember that a pound is about half a kilogram, and for shopping, that is enough. But the exact figure is 0.454, and the difference between 0.45 and 0.454 is small for a single pound and meaningful for a large batch. Ten pounds is not 4.5 kilograms, it is 4.536 kilograms, and the difference of 36 grams can matter in a precise bake or a large batch of dough. The fix is simple: for amounts under a pound, use 0.45 and do not worry; for amounts over a pound, use 0.454, or weigh in grams instead. A digital scale that reads grams removes the problem entirely, because grams are the unit the metric system is built on, and there is no conversion to get wrong.