Kilogram is 1000 gram units.
Kilograms to Ounces Converter — kg to oz
Convert Kilogram (kg) to Ounce (oz) using the exact conversion factor (1 kilogram = 35.27396195 ounce). See the formula, worked examples, conversion table, unit comparison, history, and common uses.
Kilograms to Ounces converter
Converter
Mass/Weight Converter
Convert SI mass, imperial weight, jewelry, atomic, and astronomy mass units.
Context values
Some unit families need one extra value for a physically accurate result.
An avoirdupois ounce is 1/16 pound.
Result = input x 1 / 0.02834952313.
Mass uses the kilogram as the base unit.
Reserved above the conversion cards and below the converter.
About Converting Kilograms to Ounces
Weight conversions between Kilogram and Ounce come up constantly in everyday commerce, shipping, and cooking, since US packaging is usually labeled in pounds while most of the rest of the world uses kilograms. Kilogram is typically associated with used as the standard mass unit in nearly every country except the United States and a few others that primarily use the pound., while Ounce is typically associated with united States (cooking, postal, retail).
Formula
ounces = kilograms × 35.2739619496
This factor comes from each unit's defined relationship to the category's base unit: 1 kilogram equals 1 base unit, and 1 ounce equals 0.028349523125 base units, so dividing one by the other gives the direct kilogram-to-ounce factor of 35.2739619496.
Simple example
1 kg × 35.27396195 = 35.27396195 oz
1 kilogram = 35.27396195 ounces.
Real-world example
50 kg × 35.27396195 = 1,763.698097 oz
50 kilograms = 1,763.698097 ounces.
Conversion table
| Kilogram (kg) | Ounce (oz) |
|---|---|
| 1 kg | 35.27396195 oz |
| 5 kg | 176.3698097 oz |
| 10 kg | 352.7396195 oz |
| 25 kg | 881.8490487 oz |
| 50 kg | 1,763.698097 oz |
| 100 kg | 3,527.396195 oz |
Reverse conversion: Ounce to Kilogram
35.27396195 oz × 0.02834952313 = 1 kg
35.27396195 ounces = 1 kilograms.
kilograms = ounces × 0.028349523125
For a page dedicated to this direction, see Ounce to Kilogram.
Kilogram vs. Ounce
| Aspect | Kilogram | Ounce |
|---|---|---|
| Family | SI base unit | US/imperial customary unit |
| Typical use | Pricing and labeling goods sold by weight in retail and commodity trade | US cooking and recipe measurement (small quantities) |
| Where it's used | Used as the standard mass unit in nearly every country except the United States and a few others that primarily use the pound. | United States (cooking, postal, retail) |
Understanding the Kilogram
Kilogram (kg) measures mass. The kilogram is the SI base unit of mass; every other SI mass unit is a decimal multiple or fraction of it. It is classified as a SI base unit.
Where it's used: Used as the standard mass unit in nearly every country except the United States and a few others that primarily use the pound.
Uses of the Kilogram today
- Pricing and labeling goods sold by weight in retail and commodity trade
- Dosing calculations in medicine, especially for pediatric and weight-based prescriptions
- Structural and material specification in metric-system engineering
- Scientific measurement of mass across chemistry, physics, and materials research
History of the Kilogram
The kilogram's direct predecessor was the 'grave,' defined by the French Academy of Sciences in 1793 as the mass of one cubic decimeter of water at its temperature of maximum density. Because 'grave' echoed the aristocratic title 'graf,' revolutionary France's decree of 18 Germinal, Year III (7 April 1795) renamed the system: the gram became the reference unit, defined as the mass of one cubic centimeter of water at the melting point of ice, and the kilogram — one thousand grams — took over the grave's practical role.
Turning that water-based definition into a physical object required real experimental work: chemist Louis Lefèvre-Gineau was tasked in 1795 with measuring precisely how much a cubic decimeter of water weighed, and former royal jeweller Marc-Étienne Janety then fabricated a platinum cylinder to embody that measured mass. Deposited in the French National Archives in 1799, it became known as the Kilogramme des Archives.
The metric system spread unevenly — Napoleon briefly restricted its use — but France made it compulsory in 1840, and the 1875 Metre Convention (signed by seventeen nations including the US) established the BIPM and a shared international prototype. The platinum-iridium International Prototype of the Kilogram, adopted in 1889 and nicknamed 'Le Grand K,' served as the world's mass reference for over a century.
On 20 May 2019, the kilogram was redefined by fixing the Planck constant at exactly 6.62607015 × 10⁻³⁴ joule-seconds, so it can now be realized in a laboratory (via a Kibble balance) without reference to any physical object.
Historical origin. Kilogram was not the invention of a single named person; it developed through the process described above.
Understanding the Ounce
Ounce (oz) measures mass. The avoirdupois ounce is 1/16 of a pound: exactly 28.349523125 grams. It is classified as a US/imperial customary unit.
Where it's used: United States (cooking, postal, retail) United Kingdom (informal/retail use)
Avoirdupois ounce vs. troy ounce. The everyday ounce (avoirdupois, 28.35 g) used for cooking and shipping is a different, smaller unit than the troy ounce (31.10 g) used for precious metals like gold and silver — this page uses the everyday avoirdupois ounce.
Uses of the Ounce today
- US cooking and recipe measurement (small quantities)
- US postal and shipping weight
- Precious metals (troy ounce, a related but distinct unit)
History of the Ounce
The ounce descends from the Roman 'uncia' (a twelfth part), inherited through medieval English weight systems; the avoirdupois ounce (for general goods, as opposed to the troy ounce for precious metals) became standard for everyday trade, fixed at exactly 28.349523125 g via the pound's 1959 international standardization.
Historical origin. Ounce was not the invention of a single named person; it developed through the process described above.
Kilogram — sources
- BIPM — The kilogram (SI base unit) — Official definition and history since the 2019 redefinition.
- NIST — Kilogram: The Past — History of the kilogram standard from the grave to the International Prototype Kilogram.
- SI Brochure, 9th edition (2019), Appendix 2 — BIPM — Official text of the Planck-constant-based definition of the kilogram.
Ounce — sources
- NIST — International yard and pound (1959) — Basis for the modern ounce via the standardized pound.
Reserved between the cards and the FAQ so the page stays balanced.
Frequently asked questions
How many ounces are in 1 kilogram?
1 kilogram equals 35.27396195 ounces, using the exact defined conversion factor rather than an estimate.
How do I convert kilogram to ounce?
Multiply the kilogram value by 35.27396195. The converter above does this instantly to whatever precision you set.
How do I convert ounce back to kilogram?
Use the reverse factor: 1 ounce equals 0.0283495231 kilograms. You can also use the swap control in the converter above to flip the direction instantly.
What is a kilogram?
Kilogram (kg) measures mass. The kilogram is the SI base unit of mass; every other SI mass unit is a decimal multiple or fraction of it. It is classified as a SI base unit.
What is a ounce?
Ounce (oz) measures mass. The avoirdupois ounce is 1/16 of a pound: exactly 28.349523125 grams. It is classified as a US/imperial customary unit.
Is the kilogram to ounce conversion exact?
Yes. The avoirdupois ounce is 1/16 of a pound: exactly 28.349523125 grams. That fixed definition is what the converter above uses, so any rounding you see is a display choice, not a limitation of the math.
What is the difference between avoirdupois ounce vs. troy ounce?
The everyday ounce (avoirdupois, 28.35 g) used for cooking and shipping is a different, smaller unit than the troy ounce (31.10 g) used for precious metals like gold and silver — this page uses the everyday avoirdupois ounce.
Where is the kilogram still used today?
Used as the standard mass unit in nearly every country except the United States and a few others that primarily use the pound.