Weight Converter
Convert between kilograms, pounds, ounces, grams, stones, and 20+ global mass units instantly with high scientific precision.
Last Updated: August 2026 | Reviewed by Metric & Mass Standards Team
Online Weight & Mass Calculator
Calculating exact mass conversion...
How to Use Our Weight Converter
Step-by-Step Instructions:
- 1 Enter the weight value you want to convert in the "From" input field.
- 2 Select your source weight unit (e.g., Kilogram, Pound, Gram) from the dropdown list.
- 3 Choose your target output unit in the "To" dropdown list.
- 4 View the instant calculation result and exact mathematical formula automatically.
Popular Weight Conversions:
- Kilograms to Pounds: 1 kg = 2.20462 lbs
- Pounds to Ounces: 1 lb = 16 oz
- Grams to Ounces: 100 g = 3.5274 oz
- Stones to Kilograms: 1 st = 6.35029 kg
- Metric Tons to Kilograms: 1 t = 1,000 kg
Quick Key Takeaways & Direct Answer
Direct Summary: A weight (mass) converter converts metric units (kilograms, grams, milligrams, metric tons), imperial/US units (pounds, ounces, stones, short/long tons), and scientific units (carats, grains, troy ounces, atomic mass units) using precise international conversion multipliers defined by the BIPM International System of Units and NIST Physical Measurement Laboratory.
- 1 Kilogram (kg) = 2.20462 Pounds (lbs) = 35.274 Ounces (oz)
- 1 Pound (lb) = Exactly 453.59237 Grams (g) = 16 Ounces (oz)
- 1 Stone (st) = Exactly 14 Pounds (lbs) = 6.35029 Kilograms (kg)
Audience & Use Cases
Who it is for: Freight forwarders, e-commerce sellers, fitness enthusiasts, chefs, laboratory technicians, and international travelers.
When to use: Calculating international shipping fees, converting gym weights, recipe scaling, or parcel postage verification.
Weight Unit Quick Reference & Conversion Matrix
Compare common mass and weight units against standard metric and imperial reference values:
| Unit Name | Symbol | Equivalent in Kilograms (kg) | Equivalent in Pounds (lbs) | System Standard |
|---|---|---|---|---|
| Kilogram | kg | 1.0 kg | 2.20462 lb | Metric (SI Base) |
| Pound | lb | 0.453592 kg | 1.0 lb | Imperial / US Customary |
| Gram | g | 0.001 kg | 0.00220462 lb | Metric (SI) |
| Ounce | oz | 0.0283495 kg | 0.0625 lb | Imperial / US Customary |
| Stone | st | 6.35029 kg | 14.0 lb | UK Imperial |
| Metric Ton | t | 1,000 kg | 2,204.62 lb | Metric (SI) |
Frequently Asked Questions (FAQ)
Comprehensive Guide to Weight & Mass Conversion
1. International Shipping & Logistics
In global logistics, converting between metric kilograms and imperial pounds is essential. Air cargo rates and ocean container limits depend on precise gross weight declarations. Using internationally recognized standard multipliers prevents shipping delays and customs audits.
2. E-commerce & Postal Rates
Online sellers on Amazon, eBay, or Shopify frequently ship products worldwide. Postal services require accurate weight inputs in ounces or grams for lightweight items, or pounds and kilograms for heavier parcels to calculate accurate postage rates.
3. Fitness, Health & Body Weight
Gym equipment and health tracking applications alternate between stones, kilograms, and pounds depending on regional standards (e.g. UK stone system vs US pounds vs European kilograms). Our converter makes tracking weight loss or strength benchmarks effortless.
4. Scientific & Industrial Applications
Laboratory technicians and jewelers rely on specialized mass units like carats for gemstones and troy ounces for precious metals like gold and silver. For physics applications, force measurements in newtons can also be calculated accurately.
Weight Conversion Chart - Common Units at a Glance
Use this weight conversion chart to quickly reference common mass and weight conversions between metric and imperial systems. This chart covers the most frequently searched weight conversion values.
| From | To | Multiply By | Example |
|---|---|---|---|
| Pounds (lb) | Kilograms (kg) | 0.453592 | 10 lb = 4.536 kg |
| Kilograms (kg) | Pounds (lb) | 2.20462 | 10 kg = 22.046 lb |
| Stone (st) | Kilograms (kg) | 6.35029 | 10 st = 63.503 kg |
| Kilograms (kg) | Stone (st) | 0.157473 | 70 kg = 11.023 st |
| Ounces (oz) | Kilograms (kg) | 0.0283495 | 16 oz = 0.4536 kg |
| Kilograms (kg) | Ounces (oz) | 35.274 | 5 kg = 176.37 oz |
| Grams (g) | Pounds (lb) | 0.00220462 | 500 g = 1.1023 lb |
| Milligrams (mg) | Grams (g) | 0.001 | 500 mg = 0.5 g |
| Metric Ton (t) | Pounds (lb) | 2204.62 | 1 t = 2204.62 lb |
Weight Converter lb to kg - Pounds to Kilograms
Converting pounds (lb) to kilograms (kg) is one of the most common weight conversions. The international avoirdupois pound is defined as exactly 0.45359237 kilograms. This means to convert any weight from pounds to kilograms, you simply multiply the value by 0.45359237.
Common Pound to Kilogram Conversions:
- 1 lb = 0.4536 kg
- 5 lb = 2.268 kg
- 10 lb = 4.536 kg
- 50 lb = 22.68 kg
- 100 lb = 45.36 kg
- 150 lb = 68.04 kg
- 180 lb = 81.65 kg
- 200 lb = 90.72 kg
- 250 lb = 113.4 kg
- 300 lb = 136.08 kg
This conversion is commonly used for body weight measurement, shipping parcels to countries using the metric system, and calculating gym weights when traveling internationally.
Weight Converter Stone to kg - Stones to Kilograms
The stone (st) is a unit of weight commonly used in the United Kingdom and Ireland for measuring body weight. One stone is equal to exactly 14 pounds or 6.35029318 kilograms. To convert stones to kilograms, multiply the stone value by 6.35029318.
Common Stone to Kilogram Conversions:
- 8 st = 50.80 kg
- 9 st = 57.15 kg
- 10 st = 63.50 kg
- 11 st = 69.85 kg
- 12 st = 76.20 kg
- 13 st = 82.55 kg
- 14 st = 88.90 kg
- 15 st = 95.25 kg
- 18 st = 114.31 kg
- 20 st = 127.01 kg
In the UK, body weight is traditionally measured in stones and pounds. If you weigh 12 stone 7 pounds, that is equivalent to 79.38 kg. Many NHS health resources use both stones and kilograms.
Weight Converter oz to kg - Ounces to Kilograms
Converting ounces (oz) to kilograms (kg) is essential for cooking, postal services, and product labeling. One avoirdupois ounce equals 0.0283495231 kilograms. There are 16 ounces in a pound and approximately 35.274 ounces in a kilogram.
Common Ounce to Kilogram Conversions:
- 1 oz = 0.02835 kg
- 4 oz = 0.1134 kg
- 8 oz = 0.2268 kg
- 12 oz = 0.3402 kg
- 16 oz = 0.4536 kg (1 lb)
- 24 oz = 0.6804 kg
- 32 oz = 0.9072 kg
- 48 oz = 1.3608 kg
- 64 oz = 1.8144 kg
- 100 oz = 2.835 kg
Weight Converter kg to Liter - Mass to Volume Conversion
Converting kilograms to liters requires knowing the density of the substance. Unlike weight-to-weight conversions, mass-to-volume conversion depends on what material you are measuring. For pure water at 4°C, 1 kilogram equals exactly 1 liter.
Common kg to Liter Conversions by Substance:
| Substance | Density (kg/L) | 1 kg = ? Liters |
|---|---|---|
| Water | 1.0 | 1.0 L |
| Milk | 1.03 | 0.971 L |
| Olive Oil | 0.92 | 1.087 L |
| Honey | 1.42 | 0.704 L |
| Gasoline | 0.75 | 1.333 L |
| Flour | 0.593 | 1.686 L |
| Sugar | 1.55 | 0.645 L |
This conversion is commonly used in cooking, chemical manufacturing, fuel estimation, and beverage production where you need to know how many liters a given weight of material will occupy.
Weight Converter ml to kg - Milliliters to Kilograms
Converting milliliters (ml) to kilograms (kg) also depends on the substance density. For water, 1000 ml (1 liter) equals 1 kilogram. For other liquids, you must factor in the specific gravity or density of that liquid.
Quick ml to kg Reference (Water):
- 100 ml = 0.1 kg
- 250 ml = 0.25 kg
- 500 ml = 0.5 kg
- 750 ml = 0.75 kg
- 1000 ml = 1.0 kg
- 1500 ml = 1.5 kg
- 2000 ml = 2.0 kg
- 5000 ml = 5.0 kg
Note: These values are for water. For oils, syrups, or other substances, the conversion will differ based on their specific density.
Weight Converter Related: Height & Length Conversions (kg to cm, Feet to cm)
When people search for "weight converter kg to cm" or "weight converter feet to cm", they are usually looking for height conversions to accompany their weight measurements for BMI calculation, fitness tracking, or medical records. Here are the essential height conversions:
Feet & Inches to Centimeters:
- 5'0" = 152.4 cm
- 5'4" = 162.56 cm
- 5'6" = 167.64 cm
- 5'8" = 172.72 cm
- 5'10" = 177.80 cm
- 6'0" = 182.88 cm
- 6'2" = 187.96 cm
Common cm to Feet Conversions:
- 150 cm = 4'11"
- 160 cm = 5'3"
- 165 cm = 5'5"
- 170 cm = 5'7"
- 175 cm = 5'9"
- 180 cm = 5'11"
- 185 cm = 6'1"
Weight Converter & BMI Calculator Guide
Body Mass Index (BMI) is a measure that uses your weight and height to determine if your weight is in a healthy range. Our weight converter helps you convert your body weight into the correct unit (kilograms) needed for BMI calculation.
BMI Categories (WHO Standards):
- Underweight: BMI below 18.5
- Normal weight: BMI 18.5 – 24.9
- Overweight: BMI 25.0 – 29.9
- Obese: BMI 30.0 and above
BMI Calculation Examples:
- 70 kg, 1.75 m → BMI = 22.9 (Normal)
- 85 kg, 1.80 m → BMI = 26.2 (Overweight)
- 60 kg, 1.65 m → BMI = 22.0 (Normal)
- 95 kg, 1.70 m → BMI = 32.9 (Obese)
- 55 kg, 1.60 m → BMI = 21.5 (Normal)
To calculate your BMI, first convert your weight to kilograms using our weight converter above (e.g., 154 lbs = 69.85 kg), then convert your height to meters (e.g., 5'8" = 1.7272 m), and apply the formula. BMI is a screening tool and does not directly measure body fat or overall health.
Mass and Weight Conversion Calculator - Complete Guide
Our mass and weight conversion calculator supports over 20 units from three major measurement systems: Metric (SI), Imperial/US Customary, and Scientific units. Understanding the difference between mass and weight is important for accurate conversions.
Metric Units (SI)
- • Kilogram (kg) - base unit
- • Gram (g)
- • Milligram (mg)
- • Microgram (μg)
- • Metric Ton (t)
- • Quintal (q)
Imperial / US Units
- • Pound (lb)
- • Ounce (oz)
- • Stone (st)
- • Short Ton (US)
- • Long Ton (UK)
- • Hundredweight (cwt)
Scientific Units
- • Carat (ct)
- • Troy Ounce (oz t)
- • Grain (gr)
- • Dram (dr)
- • Atomic Mass Unit (u)
- • Dalton (Da)
Mass vs. Weight:
Mass is the amount of matter in an object and remains constant regardless of location. It is measured in kilograms (kg). Weight is the force exerted on mass by gravity and varies with gravitational pull. It is technically measured in newtons (N). In everyday use, "weight" and "mass" are used interchangeably, and our converter handles both seamlessly. On Earth's surface, 1 kg of mass weighs approximately 9.807 N.