Ounces to Kilograms (oz to kg)
One ounce is exactly 0.028349523125 kilograms, so kilograms = ounces times 0.028349523125: 1 oz is 0.028349523125 kg, 8 oz is 0.226796185 kg, and 16 oz, which is one pound, is 0.45359237 kg. This page opens with ounces on the left and kilograms on the right whatever the converter was last set to, answers as you type from a field that starts at 1 or at the number you last entered, and lists the same weight in milligrams, grams, tonnes, pounds, stone and US short tons underneath, because an ounce is usually being compared with something. The ounce here is the avoirdupois ounce of food, post and kitchen scales, not the troy ounce of precious metals and not the fluid ounce, which measures volume and sits under the converter's Volume category.
1 oz in every mass unit
Common questions
- How many kilograms are in an ounce?
- Exactly 0.028349523125 kg. An ounce is a sixteenth of the international avoirdupois pound, and that pound has been defined as exactly 0.45359237 kg since 1959, so the factor is a definition rather than a measurement and the page prints every digit of it. The Copy result button copies the figure without the digit grouping, so it pastes straight into a spreadsheet.
- What is 16 oz in kg?
- 0.45359237 kg, exactly, because sixteen ounces is one pound and the pound is defined in kilograms. Type 16 into the field and the answer appears with no button press. The other kitchen amounts work the same way: 4 oz is 0.1133980925 kg, 8 oz is 0.226796185 kg, 12 oz is 0.3401942775 kg and 100 oz is 2.8349523125 kg.
- Is an ounce the same as a fluid ounce?
- No. A fluid ounce measures volume, so it converts to millilitres and litres rather than to kilograms: one US fluid ounce is 29.5735295625 mL and one imperial fluid ounce is 28.4130625 mL. Both sit under the Volume category on the strip above the converter, and this page never mixes the two dimensions, so an ounce of weight cannot turn into a litre by accident. Water is close enough that a US fluid ounce of it weighs about 29.6 g, but flour, oil and honey are not water.
- How do I convert kilograms back to ounces?
- Press the swap button between the two fields and the pair reverses to kilograms into ounces, or divide by 0.028349523125. One kilogram is 35.2739619496 oz at the twelve significant digits this page works to, and half a kilogram is 17.6369809748 oz. In your head, dividing ounces by 35 lands about 0.8 percent high, which is close enough for a parcel and not for a figure you have to match on a scale.
- Why does it show grams, pounds and stone as well?
- Because a weight is easier to judge beside the units you already use, and most converters make you pick one target before they tell you anything. Under the answer the same weight is listed in milligrams, grams, kilograms, tonnes, pounds, stone and US short tons, each with its own Copy button, and one switch in the readout adds the three rarer ones: long tons, carats and grains. For 1 oz that reads 28.349523125 g, 0.0625 lb and 0.00446428571429 st.
- Is this the ounce that gold is priced in?
- No. Bullion is weighed in troy ounces of 31.1034768 g, roughly 10 percent heavier, and the troy ounce is deliberately absent from the mass list here: converting a bullion weight with the 0.028349523125 factor would give the wrong answer, and a page offering both ounces under one name invites exactly that mistake.
- Does anything I type leave my browser?
- No. The conversion is one multiplication done in the page, with no upload and no account, and it keeps working with no network once the page has loaded. The number you last typed is kept in your own browser so the field is where you left it, Start over at the top of the page clears it, and opening this page on ounces to kilograms does not change the pair the main converter remembers.
Conversion factors are the exact legal definitions where one exists. An inch is exactly 2.54 cm and a pound exactly 0.45359237 kg, so those conversions are exact rather than approximate. Temperature uses offsets rather than factors, and that is shown in the working.