Unit Converter

Convert length, weight, temperature, area, volume and speed between any units, instantly.

Result
0.1

1 mm = 0.1 cm

Common conversions

Every conversion runs in your browser. Nothing you type is uploaded to BroBroGo.

FAQ

Which units can I convert?

Length (mm, cm, m, km, inch, foot, yard, mile), weight (mg, g, kg, ton, ounce, pound, stone), temperature (Celsius, Fahrenheit, Kelvin), area (m², ft², acre, hectare…), volume (mL, L, gallon, fl oz…) and speed (m/s, km/h, mph, knot).

Are the conversions exact?

Yes. It uses the internationally-defined exact conversion factors (e.g. 1 inch = 2.54 cm, 1 lb = 0.45359237 kg) computed in double precision, so results do not drift.

Can I convert in both directions?

Yes — pick any two units, or press the swap button to reverse them instantly.

Written and reviewed by the BroBroGo editorial team.Last updated:

How the Unit Converter Works

The Unit Converter is an interactive tool designed to perform instant conversions across six distinct measurement categories: length, weight, temperature, area, volume, and speed. To use the tool, you enter a numerical value into the input field, select the appropriate category, and choose the specific units you wish to convert from and to. The tool immediately displays the converted value.

By default, the tool loads with a preset conversion of 1 mm to 0.1 cm. If you need to reverse the direction of your calculation, you can use the swap function to instantly exchange the selected "from" and "to" units.

Input Specifications and Error Handling

To ensure accurate calculations, the input field requires specific formatting:

  • Value: You must enter a numerical value. Commas must be removed from the number.
  • Category: You select one of the six supported categories: Length, Weight, Temperature, Area, Volume, or Speed.
  • Units: You select the starting unit and the target unit from the lists available within your chosen category.

If you enter invalid text, such as "oops", or if you clear the input field entirely, the tool displays "—" in the result area. The output area is configured with aria-live="polite" to ensure that updates to the result are immediately accessible to assistive technologies.

Supported Measurement Categories and Units

The tool supports a wide range of standard units across six primary categories:

  • Length: Includes millimeter (mm), centimeter (cm), meter (m), kilometer (km), inch, foot, yard, and mile.
  • Weight: Includes milligram (mg), gram (g), kilogram (kg), ton, ounce, pound, and stone.
  • Temperature: Includes Celsius, Fahrenheit, and Kelvin.
  • Area: Includes square meters (m²), square feet (ft²), acres, and hectares.
  • Volume: Includes milliliters (mL), liters (L), gallons, and fluid ounces (fl oz).
  • Speed: Includes meters per second (m/s), kilometers per hour (km/h), miles per hour (mph), and knots.

The interface also displays a table of common conversions, which provides a quick reference for frequently used, fixed unit pairs.

Mathematical Precision and Conversion Rules

Calculations are performed using double-precision floating-point math based on internationally-defined exact conversion factors. This prevents mathematical drift and ensures high precision. Examples of these exact standards include:

  • Length: 1 inch is defined as exactly 2.54 cm.
  • Weight: 1 lb is defined as exactly 0.45359237 kg.

Absolute vs. Relative Scales in Temperature

While most physical properties like length or weight use relative scales where zero represents a complete absence of the quantity, temperature scales often involve offsets. Because of these offsets, temperature conversions cannot be calculated using a simple multiplication factor. Instead, they are handled separately using specific linear equations. For example, entering a value of 100 with Temperature selected as the category and converting from Celsius to Fahrenheit outputs 212.

Local Processing and Privacy

Your data privacy is maintained during use. Every conversion runs locally in your browser. Nothing you type into the input fields is uploaded to BroBroGo.

Practical Applications of Unit Conversions

Standardized units are essential for consistency in daily tasks, scientific work, and international trade. Manual conversions are often prone to calculation errors, making digital tools a reliable alternative for simplifying complex calculations. Common scenarios where quick unit conversions are necessary include:

  • Cooking and Recipes: Comparing liquid volumes (such as milliliters to fluid ounces) or weighing ingredients in grams versus ounces.
  • Travel Planning: Converting vehicle speeds from kilometers per hour to miles per hour, or converting travel distances from kilometers to miles.
  • Weather and Science: Understanding temperature readings on a different scale, such as converting Celsius to Fahrenheit.
  • Real Estate and Agriculture: Calculating land area in different units, such as hectares to acres.

Frequently Asked Questions

Which units can I convert? You can convert Length (mm, cm, m, km, inch, foot, yard, mile), weight (mg, g, kg, ton, ounce, pound, stone), temperature (Celsius, Fahrenheit, Kelvin), area (m², ft², acre, hectare…), volume (mL, L, gallon, fl oz…) and speed (m/s, km/h, mph, knot).

Are the conversions exact? Yes. It uses the internationally-defined exact conversion factors (e.g. 1 inch = 2.54 cm, 1 lb = 0.45359237 kg) computed in double precision, so results do not drift.

Can I convert in both directions? Yes — pick any two units, or press the swap button to reverse them instantly.

What happens if I enter an invalid value? If you enter invalid text like "oops" or leave the input field empty, the tool will display "—" as the result.

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