Weight Conversion Calculator

How to use this calculator

Enter your values in the fields above and click Calculate to see your results instantly. All calculations run in your browser — no data is sent to a server and results appear immediately. Click Clear to reset all fields and start over.

Understanding your inputs

Each input field is labeled with the specific value it expects. Hover over the ? hint icons (where present) for additional guidance on what each field means and what units to use. For best results, double-check that all your input values use consistent units before calculating.

Interpreting the results

Results are shown immediately after clicking Calculate. The highlighted result card shows the primary output — the value most people need. Additional cards show supporting calculations that provide context and help you verify the primary result makes sense. If results seem unexpected, re-check your inputs for typos or unit mismatches.

About this unit conversion calculator

This calculator implements standard unit conversion formulas used by professionals and students alike. The underlying math has been verified against reference implementations and textbook examples. For critical applications, always cross-reference results with authoritative sources or a qualified professional.

Weight Conversion Chart: Complete Reference Table

Use the table below as a quick reference for converting between common weight units. All values show how many grams are in one unit of each measurement.

Unit	Abbreviation	Grams (g)	Kilograms (kg)
Milligram	mg	0.001	0.000001
Gram	g	1	0.001
Kilogram	kg	1,000	1
Ounce	oz	28.3495	0.028350
Pound	lb	453.592	0.453592
Stone	st	6,350.29	6.35029
Metric Ton (tonne)	t	1,000,000	1,000
Short Ton (US)	ton	907,185	907.185

How Many Pounds in a Kilogram?

The kilogram-to-pound conversion is one of the most searched weight questions online. The exact relationship is: 1 kilogram = 2.20462 pounds, and going the other direction: 1 pound = 0.453592 kilograms.

These conversions are defined by international treaty. The pound was officially defined as exactly 0.45359237 kg in 1959 by the International Yard and Pound Agreement, which means every kg-to-lb calculation derives from that exact figure.

Kilograms to Pounds — Common Body Weights

Kilograms (kg)	Pounds (lb)	lb & oz
50 kg	110.231 lb	110 lb 3.7 oz
60 kg	132.277 lb	132 lb 4.4 oz
70 kg	154.324 lb	154 lb 5.2 oz
80 kg	176.370 lb	176 lb 5.9 oz
90 kg	198.416 lb	198 lb 6.7 oz
100 kg	220.462 lb	220 lb 7.4 oz

Pounds to Kilograms — Common Body Weights

Pounds (lb)	Kilograms (kg)
100 lb	45.359 kg
120 lb	54.431 kg
140 lb	63.503 kg
150 lb	68.039 kg
160 lb	72.575 kg
180 lb	81.647 kg
200 lb	90.718 kg

Stones and Pounds: UK Weight Conversions

The stone is a unit of weight used almost exclusively in the United Kingdom and Ireland to express body weight. 1 stone = 14 pounds = 6.35029 kilograms. If you see a UK person's weight listed as "12 stone 4" that means 12 stones plus 4 additional pounds.

Stone (st)	Pounds (lb)	Kilograms (kg)
8 st	112 lb	50.802 kg
9 st	126 lb	57.153 kg
10 st	140 lb	63.503 kg
11 st	154 lb	69.853 kg
12 st	168 lb	76.204 kg
13 st	182 lb	82.554 kg
14 st	196 lb	88.904 kg

Frequently Asked Questions

How precise are these conversions?

These conversions use standard international definitions and are precise to the limits of floating-point arithmetic (typically 15 significant figures). For most practical purposes (engineering, cooking, everyday use) this precision far exceeds what's needed. Scientific calculations requiring extreme precision should use specialized software with arbitrary precision arithmetic.

Why do some conversion factors look odd?

Many conversion factors between imperial and metric units are defined by exact treaty definitions (e.g., 1 inch = exactly 25.4 mm since 1959). Others are derived quantities with irrational decimal expansions. The seemingly odd numbers reflect historical accident — the systems were developed independently and unit relationships weren't designed to be round numbers.

What is the difference between mass and weight?

Mass is a measure of how much matter an object contains (kilograms, grams, pounds-mass) and doesn't change with gravity. Weight is a force equal to mass × gravitational acceleration (newtons, pounds-force). In everyday use on Earth's surface the distinction rarely matters, but it becomes critical in engineering, aerospace, and scientific contexts.

How do I convert temperatures correctly?

Temperature conversions require both scaling and shifting, unlike most unit conversions. Fahrenheit to Celsius: subtract 32, multiply by 5/9. Celsius to Kelvin: add 273.15. Kelvin is the SI base unit — always positive and starts at absolute zero. For temperature differences (not absolute temperatures), you only need the scaling factor: 1°C change = 1.8°F change.

How many pounds in a kilogram?

There are exactly 2.20462 pounds in one kilogram. This conversion is derived from the international definition of the pound (1 lb = 0.45359237 kg exactly, set by treaty in 1959). To convert kilograms to pounds, multiply by 2.20462. For example, 70 kg × 2.20462 = 154.324 lb.

How many kg in a pound?

There are exactly 0.453592 kilograms in one pound (more precisely 0.45359237 kg). To convert pounds to kilograms, multiply by 0.453592. For example, 150 lb × 0.453592 = 68.039 kg.

How many ounces in a pound?

There are exactly 16 ounces (oz) in one pound (lb). This is a fixed relationship in the avoirdupois system used in the US and UK for everyday weights. So 1 lb = 16 oz, 2 lb = 32 oz, and so on. One ounce equals approximately 28.3495 grams.

How many grams in an ounce?

There are approximately 28.3495 grams in one ounce (more precisely 28.349523125 g). This is a standard avoirdupois ounce. Note that a troy ounce (used for precious metals like gold and silver) is slightly heavier at 31.1035 grams.

What is a stone in pounds and kg?

A stone is a unit of weight used mainly in the UK and Ireland. 1 stone = 14 pounds = 6.35029 kilograms. Body weight in the UK is often expressed as a combination of stones and pounds — for example, "11 stone 5" means 11 × 14 + 5 = 159 pounds, or about 72.1 kg.

Common Tip Percentages

Service	Typical Tip Range	Notes
Restaurant (sit-down)	15–20%	20%+ for exceptional service
Food delivery	10–20%	Consider extra for long distances
Taxi / rideshare	10–20%	More for assistance with luggage
Hotel housekeeping	$2–5/night	Leave daily, not just at checkout
Barber / hair salon	15–20%	On pre-discount total
Pizza delivery	10–15% or $3–5 minimum	Higher in bad weather

General Household Budget Ratios (50/30/20 Rule)

Category	% of Net Income	Examples
Needs	50%	Rent, groceries, utilities, insurance
Wants	30%	Dining out, entertainment, hobbies
Savings / Debt	20%	Emergency fund, retirement, extra payments

Common Measurement Conversions for Everyday Use

Quantity	US / Imperial	Metric Equivalent
1 cup	8 fl oz	237 mL
1 pint	16 fl oz	473 mL
1 quart	32 fl oz	946 mL
1 gallon	128 fl oz	3.785 L
1 lb	16 oz	453.6 g
1 ft	12 in	30.48 cm