Measurement made clearer
Convert units of length, weight, volume, and temperature.
Enter a number, then choose the units to convert between. Switch between inches and centimeters, pounds and kilograms, cups and liters, or temperature scales.
Your conversion
Enter a value to convert.
The converted number and method will appear here.
Your conversion
Method
Keep the unit attached
A number without a unit is incomplete. Length, area, volume, mass, and temperature are different kinds of measurement; converting within one kind does not make them interchangeable.
Worked length example
12 inches equals 30.48 centimeters. The number changes, but the measured length does not.
Weight versus volume
An ounce of mass is not the same as a fluid ounce of volume. Converting between them requires the material’s density.
Temperature is different
Fahrenheit, Celsius, and Kelvin conversions use both a scale interval and an offset. They are not simple multiplication-only conversions.
Assumptions and limits
This tool uses common reference conversions and U.S. liquid measures. Results are rounded for display, while the calculation keeps additional precision internally. It does not convert between mass and volume, account for material density, identify a fastener, or determine whether a measurement is suitable for a structural, automotive, electrical, medical, or other safety-critical use. Check the product specification or a qualified professional when precision or compatibility matters.
Method reviewed September 29, 2026.
Learn mode
A conversion changes the number, not the thing
Try this question: Is 12 inches longer than 30.48 centimeters?
Think first: No. They describe the same length in different units, so the numbers differ while the measured length stays equal.
The method: 12 inches × 2.54 centimeters per inch = 30.48 centimeters.
Remember: Keep the unit attached, and never treat length, area, volume, mass, and temperature as interchangeable.
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