Convert Ounce to Kilogram

Quick answer: Ounce to Kilogram

1 Ounce = 0.02834952 Kilogram (oz → kg). To convert ounce to kilogram, multiply by 0.02834952. To convert kilogram to ounce, multiply by 35.27396. The converter at the top does this instantly and both ways; the sections below give the formula, worked examples, a full conversion chart and answers to the most common ounce-to-kilogram questions.

How to convert Ounce to Kilogram

To convert ounce to kilogram, multiply the number of ounce by the conversion factor 0.02834952, because 1 oz = 0.02834952 kg. The conversion is linear, so the same factor works for any value — whole numbers, decimals or fractions. For the reverse direction, 1 kg = 35.27396 oz, so you divide by 0.02834952 (or multiply by 35.27396) to turn kilogram back into ounce.

kg = oz × 0.02834952  ·  oz = kg × 35.27396

1. Write down the value you want to convert, in ounce.
2. Multiply it by 0.02834952.
3. The result is the same area/length/quantity expressed in kilogram.

Ounce to Kilogram — worked examples

Each row shows the exact arithmetic so you can follow the conversion step by step. For example, 5 ounce is 0.1417476 kilogram because 5 oz × 0.02834952 = 0.1417476 kg.

Common Ounce to Kilogram conversions

These are the ounce-to-kilogram values people look up most often. Every figure is computed from the exact factor, so you can rely on them for quick reference:

• 1 ounce = 0.02834952 kilogram
• 2 ounce = 0.05669905 kilogram
• 2.5 ounce = 0.07087381 kilogram
• 3 ounce = 0.08504857 kilogram
• 4 ounce = 0.1133981 kilogram
• 5 ounce = 0.1417476 kilogram
• 6 ounce = 0.1700971 kilogram
• 7 ounce = 0.1984467 kilogram
• 8 ounce = 0.2267962 kilogram
• 9 ounce = 0.2551457 kilogram
• 10 ounce = 0.2834952 kilogram
• 12 ounce = 0.3401943 kilogram
• 15 ounce = 0.4252428 kilogram
• 20 ounce = 0.5669905 kilogram
• 25 ounce = 0.7087381 kilogram
• 30 ounce = 0.8504857 kilogram
• 50 ounce = 1.417476 kilogram
• 75 ounce = 2.126214 kilogram
• 100 ounce = 2.834952 kilogram
• 200 ounce = 5.669905 kilogram
• 500 ounce = 14.17476 kilogram
• 1000 ounce = 28.34952 kilogram

Ounce to Kilogram conversion chart (both directions)

The chart below converts ounce to kilogram and kilogram to ounce side by side, so it works whichever way you need. 1 ounce = 0.02834952 kilogram, and 1 kilogram = 35.27396 ounce.

Ounce vs Kilogram: which is bigger?

A kilogram is the larger unit: one kilogram equals 35.27396 ounces. Put another way, you need 35.27396 ounces to make a single kilogram.

What is a Ounce? History, origin and usage

The ounce comes from the Latin uncia, meaning a twelfth part — originally a twelfth of the Roman libra. English later reorganised its weights around the avoirdupois system, in which the pound is divided into sixteen ounces rather than twelve, and that sixteenth is the ounce used for ordinary goods today.

Ounces are used for food packaging, recipes, letters and small parcels in the United States, and for some foods and postal rates in the United Kingdom. Recipe writers use them constantly for butter, flour and cheese.

The same Latin root uncia also gave English the word "inch" — a twelfth of a foot. Confusingly, the troy ounce used for gold is a different and heavier ounce, and a "fluid ounce" is a measure of volume, not weight at all.

What is a Kilogram? History, origin and usage

The kilogram began in revolutionary France in 1795 as the mass of a litre of water at the temperature where water is densest. In 1889 that idea was replaced by a physical object: the International Prototype of the Kilogram, a platinum-iridium cylinder kept in a vault at Sèvres near Paris. For 130 years the kilogram was whatever that one lump of metal weighed. The problem was that the official copies slowly drifted apart from it by tens of micrograms, so on 20 May 2019 the definition was cut loose from the object and tied instead to a fixed value of the Planck constant.

The kilogram is the SI base unit of mass and the working weight unit for almost the whole world — shopping, medicine, freight, engineering and science. Every other unit on this page, metric or imperial, is defined by how many kilograms it equals, which is why the conversions here are exact rather than rounded.

It is the only SI base unit whose name carries a prefix built in ("kilo" + "gram"), a historical accident that means the SI prefix rules have to be applied to the gram instead. It was also the last base unit still defined by a man-made object, and the only one that could be scratched, cleaned or dropped.

Convert 1 Ounce to other units

It can help to see a ounce next to the other units it is commonly compared with. One ounce (oz) is equal to:

Convert 1 Kilogram to other units

One kilogram (kg) is equal to:

Tips for converting Ounce to Kilogram

• To go from ounce to kilogram, multiply by 0.02834952; to go back, divide by 0.02834952 (or multiply by 35.27396).
• For a quick mental estimate, remember that 1 ounce ≈ 0.02834952 kilogram, so 10 ounce ≈ 0.2834952 kilogram.
• The converter above keeps full precision; the tables round for readability, so use the tool for exact figures.
• Both fields update live as you type — change either side to convert in that direction.

How to use this Ounce to Kilogram converter

Type a number into the Ounce field and the equivalent in Kilogram appears instantly — there is no “convert” button to press and nothing is sent to a server, so it works offline once the page has loaded and is safe for any data. You can also type into the Kilogram field to convert the other way (kilogram to ounce). Use the swap control to flip the two units, and copy the result with a single click. Because the calculation runs in your browser with full floating-point precision, the converter is more exact than the rounded figures shown in the reference chart above — use the chart for quick look-ups and the tool for precise work.

Accuracy and method

Every figure on this page — the formula, the worked examples, the conversion chart and the “convert to other units” tables — is computed from a single verified conversion factor (1 oz = 0.02834952 kg), never copied from a hand-typed lookup table that could drift. That factor is derived from each unit’s definition in terms of a common base unit, and an automated check re-verifies all of the site’s factors on every update, so the numbers here stay correct over time. This matters for ounce-to-kilogram conversions because a small rounding error in a published table compounds quickly at larger quantities; computing from the exact factor avoids that.

Sources

• NIST Special Publication 811 — Guide for the Use of the SI — publishes the exact metric equivalents of the customary weight units. The 1959 international yard-and-pound agreement fixes the international avoirdupois pound at exactly 0.453 592 37 kilogram, and the ounce, stone, grain and both tons are defined as exact fractions or multiples of that pound — so every imperial weight on this page is exact, not rounded.
• BIPM — The International System of Units (SI Brochure) — the defining document for the SI, published by the International Bureau of Weights and Measures. It fixes the base unit that this conversion resolves to, which is why the factor here can be exact rather than approximate.

Weight factors here are exact, anchored to the kilogram: the international pound is exactly 0.45359237 kg, a stone is 14 pounds, a short ton is 2,000 pounds and a long ton is 2,240, a grain is 1/7000 of a pound and a metric carat is exactly 200 mg. So the live tool and every number on this page always agree.

Frequently asked questions

How many kilogram are in 1 ounce?

1 ounce = 0.02834952 kilogram (kg). To convert any number of ounce to kilogram, multiply by 0.02834952.

How do I convert ounce to kilogram?

Multiply the number of ounce by 0.02834952. For example, 10 ounce = 10 × 0.02834952 = 0.2834952 kilogram, and 25 ounce = 0.7087381 kilogram.

How many ounce are in 1 kilogram?

1 kilogram = 35.27396 ounce. So to convert kilogram back to ounce, multiply by 35.27396.

What is the formula to convert ounce to kilogram?

kilogram = ounce × 0.02834952. The reverse formula is ounce = kilogram × 35.27396.

How much is 100 ounce in kilogram?

100 ounce = 2.834952 kilogram. (And 1000 ounce = 28.34952 kilogram.)

Which is bigger, a ounce or a kilogram?

A kilogram is larger: 1 kilogram = 35.27396 ounce.

Is this ounce to kilogram converter accurate?

Yes — every value is computed from the exact 0.02834952 kg per oz factor (not rounded look-up tables), and the factors are re-verified automatically on every update.

Can I convert kilogram to ounce too?

Yes. The converter works both ways — enter a value in either field. 1 kilogram = 35.27396 ounce.

Related weight conversions

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• Pound to Kilogram
• Gram to Ounce
• Ounce to Gram
• Kilogram to Stone
• Stone to Kilogram
• Pound to Ounce
• Ounce to Pound
• Gram to Kilogram

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