Mass Calculator
Convert mass between kilograms, pounds, ounces, grams, and other units.
Mass Calculator
Convert mass between kilograms, pounds, ounces, grams, and other units.
Unit Conversion
ℹ️ All units normalised to a common base before converting to ensure accuracy
Disclaimer
Results provided by this calculator are for informational and educational purposes only. They are based on the values you enter and standard formulas, and should not be considered financial, medical, legal, or professional advice. Always consult a qualified professional before making important decisions based on these results. Roughtools makes no warranties regarding the accuracy or completeness of these calculations for your specific situation.
Frequently Asked Questions
Pro Tips
Always double-check your unit conversion direction — dividing when you should multiply (or vice versa) produces a result off by the conversion factor squared.
For temperature conversions, remember the formulas differ: Celsius to Fahrenheit = (C × 9/5) + 32. Fahrenheit to Celsius = (F − 32) × 5/9. Kelvin = Celsius + 273.15.
Imperial units have multiple definitions (fluid ounce vs weight ounce, US vs UK gallon). Always confirm which system applies — especially for cooking or scientific work.
Significant figures matter in scientific conversions. If your input has 2 significant figures, don't report 6 decimal places of precision — it implies false accuracy.
When to Use This Calculator
Convert between metric and imperial units for temperature, distances, weights, and speeds when travelling abroad.
Convert between US and metric measurements for international recipes or ingredient scaling.
Convert units for scientific calculations where SI units are required.
Convert between measurement systems when working with international suppliers or standards.
Convert units to compare product sizes and prices across different packaging formats.
About the Mass Calculator
This mass calculator converts any mass value between all common units — kilograms (kg), pounds (lb), ounces (oz), grams (g), milligrams (mg), metric tons (tonne), short tons, long tons, stones, and carats — in both directions simultaneously. Enter any mass value in any unit to instantly see its equivalent in every other unit. Built for cooking, shipping, chemistry, medical dosing, and international commerce where different mass units are standard.
How to Use the Mass Calculator
- 1
Enter the mass value you want to convert.
- 2
Select the input unit (kg, lb, oz, g, tonne, stone, etc.).
- 3
See instant conversions into all other mass units simultaneously.
- 4
Click any result to use it as the new input for chained conversions.
- 5
Use the precision slider to control the number of decimal places shown.
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