Measurement · Units

Weight Converter

Convert kg ↔ lbs and other mass units with exact international factors.

  • Kilograms (kg)1
  • Grams (g)1000
  • Milligrams (mg)1000000
  • Pounds (lb)2.20462262185
  • Ounces (oz)35.2739619496
  • Stone (st)0.157473044418
  • Metric tons (t)0.001

What is Weight Converter?

This weight converter translates values among kilograms, grams, milligrams, pounds, ounces, stone, and metric tons. More precisely, these are units of mass. Everyday English commonly calls mass “weight,” which is why scales and product labels use terms such as body weight or shipping weight.

Mass describes the amount of matter and remains the same when location changes. Weight is a force caused by gravity and, in physics, is measured in newtons. A 70-kilogram person has the same mass on Earth and the Moon but a different weight force because lunar gravity is weaker.

The converter uses kilograms as its common base and the international avoirdupois definitions for pounds and ounces. It is suitable for food quantities, body mass, parcels, laboratory-scale comparisons, and international product specifications.

Why Use This Tool?

Metric and customary mass units frequently meet in recipes, fitness records, commerce, shipping, and manufacturing. Converting them accurately helps ensure that a quantity ordered, packed, or documented means the same thing to every reader.

The all-unit table is especially useful when several audiences need different formats. One entry can show kilograms for a technical sheet, pounds for a U.S. customer, and stone for a UK body-mass reference.

  • Convert kilograms to pounds and pounds to kilograms
  • Translate small gram or milligram quantities
  • Compare stone, pounds, and metric tons
  • Use exact international pound and ounce definitions

How Does This Tool Work?

The calculator multiplies the entered value by the source unit’s kilogram factor, then divides by the destination factor. One international avoirdupois pound is exactly 0.45359237 kilogram, and one avoirdupois ounce is exactly 1/16 pound, or 0.028349523125 kilogram.

Stone is represented as 14 pounds, equal to 6.35029318 kilograms. The metric ton is 1,000 kilograms. The tool does not include U.S. short tons, UK long tons, troy ounces, or force units, so labels matter when the word “ton” or “ounce” appears in a source.

Understanding Your Results

Every row reports the same mass in a different unit. For example, 1 kilogram is about 2.20462 pounds and 35.274 ounces. The number grows when the destination unit is smaller.

Results may contain more digits than a scale can actually measure. If a kitchen scale reads to the nearest gram, converting that reading does not create milligram accuracy. Round the final value according to the source measurement and its purpose.

Why Tracking This Matters

Confusing mass systems can spoil recipes, cause shipping estimates to be wrong, or introduce serious errors into technical work. Distinguishing mass from gravitational force also keeps scientific formulas dimensionally correct.

Benefits of Using Weight Converter

  • Seven common metric and avoirdupois units
  • Exact pound and ounce relationships
  • Clear support for stone and metric tons
  • One input produces a complete comparison table
  • Browser-side calculation without uploads
  • Useful across household, commercial, and educational tasks

How Is the Result Calculated?

Linear mass conversions use kilograms as the common base. Physical weight force is a separate calculation that also requires local gravitational acceleration.

destination mass = source mass × source-to-kilogram factor ÷ destination-to-kilogram factor

Mass
Amount of matter, expressed here in kg, g, mg, lb, oz, st, or metric t.
Conversion factor
Kilograms represented by one unit.
Weight force
In physics, W = m × g and is measured in newtons; this tool does not calculate it.
  • Example: 10 lb × 0.45359237 = 4.5359237 kg
  • Example: 70 kg ÷ 0.45359237 ≈ 154.324 lb

Tips for Better Results

  • Check whether “ton” means metric ton, U.S. short ton, or UK long ton.
  • Check whether an ounce is avoirdupois mass, troy mass, or a fluid ounce.
  • Use the volume converter for fluid ounces; they measure volume, not mass.
  • Preserve more digits during calculation and round only the final answer.
  • For medication or laboratory work, follow validated procedures and calibrated instruments.
  • Use newtons when a physics problem asks for weight as force.

Standards and References

Conclusion

Use this converter for common mass values labeled as weight in daily life. It provides consistent conversions among kilograms, pounds, ounces, stone, and related units.

For scientific work, remember that mass and weight force are different quantities, and verify specialized ton or ounce definitions before converting.

Privacy & how it works

This unit converter runs in your browser. Values you enter are not uploaded to The ToolSphere servers for this tool. Privacy Policy.

FAQ

Is a pound exactly 0.45359237 kilograms?expand_more

Yes. The international avoirdupois pound is defined as exactly 0.45359237 kilogram.

What is the difference between mass and weight?expand_more

Mass is the amount of matter. Weight is gravitational force on that mass. This everyday “weight” converter actually converts mass units.

How many ounces are in a pound?expand_more

There are exactly 16 avoirdupois ounces in one avoirdupois pound.

How many pounds are in a stone?expand_more

One stone equals exactly 14 avoirdupois pounds, or 6.35029318 kilograms.

Is a metric ton the same as a U.S. ton?expand_more

No. A metric ton is 1,000 kilograms. A U.S. short ton is 2,000 pounds and is not included here.

Does this tool convert troy ounces?expand_more

No. It uses avoirdupois ounces. Troy ounces, commonly used for precious metals, have a different mass.

Can mass be negative?expand_more

Ordinary physical mass is nonnegative. The calculator accepts signed numbers mathematically, but interpret them according to your specific model.

Why do converted results show many decimals?expand_more

Customary and metric units do not usually align at whole values. Round to the precision justified by your original measurement.

Is this calculator free?expand_more

Yes. No signup required.

Are my numbers uploaded?expand_more

No. Calculations run in your browser. Inputs are not sent to The ToolSphere servers for this tool.

Is this professional advice?expand_more

No. Results are estimates for general information. See our Disclaimer for health, finance, and related tools.

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