Kilogram to Gram Converter
Quickly convert from Kilogram to Gram.
How to convert
Formula:
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Mass is the measure of the amount of matter an object contains and is a measure of its inertia. Unlike weight, mass remains constant regardless of gravity.
Where is it used?
In chemistry and pharmacy for precise measurements (mg), in food commerce (kg), and in industry for large loads (tons).
Examples:
• One liter of water weighs approximately 1 kilogram.
• 1 pound (lb) is about 453.6 grams.
• An average adult has a mass around 70-80 kg.
Mass affects everything from cooking recipes to industrial shipping. Whether you need to convert pounds to kilograms for a gym workout, ounces to grams for a recipe, or understand the difference between mass and weight, this tool gives you instant, accurate results.
Mass is a fundamental property of matter — it measures how much matter an object contains and determines its resistance to acceleration (inertia). Unlike weight, which depends on gravity, mass is constant everywhere in the universe. The SI base unit is the kilogram, redefined in 2019 using the Planck constant.
Where is it used?
- Cooking & Baking — Grams and ounces for precise ingredient measurements.
- Healthcare & Pharmacy — Milligrams for drug dosages; kilograms for body weight.
- Commerce & Shipping — Kilograms and pounds for product weights; metric tons for cargo.
- Jewelry — Carats for gemstones (1 carat = 200 mg); troy ounces for precious metals.
- Science — Atomic mass units for molecules; kilograms for laboratory experiments.
Common Conversion Mistakes
Confusing mass with weight
Mass (kg) measures matter; weight (Newtons) measures gravitational force. An 80 kg person weighs about 784 N on Earth but only 130 N on the Moon — their mass stays 80 kg.
Mixing up ounces and troy ounces
A regular (avoirdupois) ounce is 28.35 g, but a troy ounce is 31.10 g. Gold and silver prices are always quoted per troy ounce — using the wrong conversion means a ~10% pricing error.
Using "ton" without specifying which one
A metric ton = 1,000 kg. A US (short) ton = 907 kg. A UK (long) ton = 1,016 kg. Always specify which "ton" you mean, or you could be off by up to 12%.
Rounding pounds to kilograms as 1 lb = 0.5 kg
1 lb actually equals 0.4536 kg. Rounding to 0.5 kg gives a 10% error — for a 150 lb person, that's a 7 kg difference (68 kg vs 75 kg).
Quick Reference Table
| From | To |
|---|---|
| 1 ounce (oz) | 28.35 g |
| 1 pound (lb) | 453.6 g |
| 1 stone | 6.35 kg |
| 1 kilogram | 2.205 lb |
| 1 metric ton | 2,205 lb |
| 1 carat | 200 mg |
| 1 troy ounce | 31.10 g |
| 1 slug | 14.59 kg |
Frequently Asked Questions
What is the difference between mass and weight?
Mass is an intrinsic property of matter measured in kilograms. Weight is the force of gravity acting on that mass, measured in Newtons. On Earth, we often use them interchangeably in daily life, but they are physically different. Your mass is the same on the Moon, but your weight is about 1/6th.
Why was the kilogram redefined in 2019?
Until 2019, the kilogram was defined by a physical platinum-iridium cylinder stored in Paris (the International Prototype of the Kilogram). This artifact could gain or lose atoms over time. The 2019 redefinition ties the kilogram to the Planck constant (h = 6.62607015 × 10⁻³⁴ J·s), making it universally reproducible.
What is a stone and where is it used?
A stone equals 14 pounds (about 6.35 kg). It's primarily used in the UK and Ireland for expressing body weight. For example, a person might say they weigh "11 stone 4" meaning 11 stones and 4 pounds (about 72 kg).
How many grams are in a pound?
One pound equals exactly 453.59237 grams. This is the international avoirdupois pound, agreed upon in 1959 by the US, UK, Canada, Australia, New Zealand, and South Africa.
What is the difference between a regular ounce and a troy ounce?
A regular (avoirdupois) ounce equals 28.3495 grams, while a troy ounce equals 31.1035 grams — about 10% heavier. Troy ounces are used exclusively for precious metals (gold, silver, platinum). Confusingly, a troy pound (12 troy oz) is lighter than an avoirdupois pound (16 oz).
Sources & Standards
- National Institute of Standards and Technology (NIST)
- International Bureau of Weights and Measures (BIPM) — 2019 SI Redefinition
- International Avoirdupois Pound Agreement, 1959
Reviewed by The Unit Hub Editorial Team · March 2026