Foundations
Metric vs Imperial Units: A Practical Comparison
Understand how metric, US customary, and Imperial units differ, where each system is used, and how to convert between them reliably.
Read guide →716 focused conversion pages · free to use
Every unit conversion,
clearly explained.
Convert instantly, see the exact formula, and check common reference values.
Quick results are rounded to a maximum of 6 decimal places. Conversion pages include adjustable precision and the complete rounding policy.
Popular conversions:Centimeters to inchesKilograms to poundsCelsius to FahrenheitLiters to US gallonsMiles per hour to km/h
✓ No sign-up✓ Runs in your browser✓ Exact formulas included
12 units
Length
Meters, feet, inches, miles, nautical miles and more.
Explore length →11 units
Weight
Kilograms, pounds, ounces, stones and metric tons.
Explore weight →4 units
Temperature
Celsius, Fahrenheit, Kelvin, and Rankine.
Explore temperature →21 units
Volume
Liters, gallons, cups, fluid ounces and cubic units.
Explore volume →7 units
Speed
Kilometers per hour, mph, knots and meters per second.
Explore speed →Reviewed relationships
One consistent source of truth
Static by default
Fast pages, no server wait
Accessible tools
Keyboard and mobile friendly
Conversion guides
Understand the units,
not just the answer.
Everyday conversions
US Gallons vs Imperial Gallons: What Is the Difference?
Compare US liquid gallons and Imperial gallons, understand their exact liter values, and avoid common fuel and recipe conversion errors.
Read guide →Science and engineering
Celsius, Fahrenheit, Kelvin, and Rankine Explained
Learn how the four major temperature scales differ, why offsets matter, and which formulas convert between them correctly.
Read guide →Why Convr?
Fast answers,
useful context.
Each conversion page combines an instant calculator with the exact relationship, common reference values, and related conversions—without sign-up or unnecessary clutter.
How Convr works →Enjoy Convr? Follow us on Google
Add convr.tools as a Preferred Source so our converters and guides show up first in Google Search, Top Stories, AI Overviews and Discover.
Add as a preferred source on Google