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Weight Converter

Free Weight Converter - calculate instantly with our online tool. No signup required. Accurate unit converters calculations with real-time results.

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How to Use the Weight Converter

  1. 1. Enter a value in the "From" field to begin your conversion.
  2. 2. Select your units - choose the source and target units from the dropdown menus.
  3. 3. View instant results - the conversion updates automatically as you type.
  4. 4. Swap direction - click the swap button to reverse the conversion.
  5. 5. Share your results - copy the link to save or share your conversion.

Weight Converter

Convert between milligrams, grams, kilograms, ounces, pounds, stone, US tons, and metric tonnes. This weight converter handles everything from small lab measurements in milligrams to shipping weights in metric tonnes, making it useful for cooking, fitness tracking, science, and commerce.

How Weight Conversion Is Calculated

All weight units convert through grams as a common base. The formula is: result = value x (source factor / target factor). Key factors: 1 kg = 1,000 g, 1 oz = 28.3495 g, 1 lb = 453.592 g, 1 stone = 6,350.29 g, 1 US ton = 907,185 g, and 1 metric tonne = 1,000,000 g.

Example

FromValueToResult
150 lbs150kg68.04
80 kg80lbs176.37
1 stone1lbs14
5 oz5g141.75
2,000 lbs2,000Metric tonnes0.907

Key Factors in Weight Conversions

  • Pounds vs. kilograms — the most common conversion worldwide; 1 kg = 2.205 lbs
  • Stone — used in the UK and Ireland for body weight; 1 stone = 14 pounds
  • US ton vs. metric tonne — a US ton is 2,000 lbs (907 kg), while a metric tonne is 1,000 kg (2,205 lbs)
  • Ounces and grams — used for food portions, postal weights, and cooking measurements
  • Precision — milligrams are critical in pharmacy and laboratory settings

Tips

  1. For a quick pounds-to-kilograms estimate, divide pounds by 2.2 — for example, 180 lbs is about 81.8 kg
  2. If you track body weight in stone (common in the UK), multiply by 14 to get pounds or by 6.35 to get kilograms
  3. When shipping internationally, always use kilograms and metric tonnes since most countries use the metric system
  4. For cooking conversions, note that 1 ounce is about 28 grams — useful when scaling recipes between US and metric measurements

Frequently Asked Questions

How do I convert kilograms to pounds?
Multiply the kilogram value by 2.20462 to get pounds. For example, 70 kg x 2.205 = 154.3 lbs. For a quick mental estimate, double the kg value and add 10% -- so 70 kg becomes 140 + 14 = 154 lbs. To convert pounds to kilograms, divide by 2.205 or multiply by 0.4536.
What is the difference between metric and imperial weight units?
The metric system uses grams and kilograms (based on powers of 10), while the imperial system uses ounces, pounds, and tons. Key relationships: 1 kg = 2.205 lbs, 1 lb = 16 oz, and 1 oz = 28.35 g. Most countries use metric exclusively, while the US uses imperial for everyday measurements and metric for science and medicine.
What are troy ounces and how do they differ from regular ounces?
A troy ounce (31.1035 g) is heavier than a standard avoirdupois ounce (28.3495 g) and is used exclusively for precious metals like gold, silver, and platinum. When you see gold priced 'per ounce,' it always means troy ounces. There are 12 troy ounces in a troy pound, compared to 16 regular ounces in a standard pound.
How do I convert cooking weights between cups and grams?
Cup-to-gram conversions vary by ingredient because they depend on density. For example, 1 cup of all-purpose flour is about 125 g, while 1 cup of sugar is about 200 g, and 1 cup of butter is about 227 g. For precise baking, especially with European recipes, a kitchen scale measuring in grams is far more accurate than volume-based cups.
Why do weight measurements differ between countries?
Weight measurement differences stem from the historical development of separate measurement systems. The US uses pounds and ounces, the UK uses a mix of stones, pounds, and metric, and most other countries use kilograms and grams exclusively. Body weight is a good example: Americans say 150 lbs, Britons say 10 stone 10 lbs, and most Europeans say 68 kg -- all describing the same weight.

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