Convert length, weight, temperature and volume with value, source unit, target unit and step-by-step solution.
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Enter values
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LengthConvert length via a base unit.
The numeric value to be converted.
Load example
For illustration only – your own calculation is what counts.
Explanation
How Unit Converter works
The unit converter uses a shared base unit per unit group. The entered value is first converted to the base and then to the target unit.
For length, weight and volume, a conversion factor is sufficient. Temperature is different: an addition or subtraction is also needed because the scales have different zero points.
The available units are deliberately limited to common everyday and work cases. This keeps the calculator quick to use and the step-by-step solution easy to follow.
Linear unitsTarget value = Value x Source factor / Target factor
Length, weight and volume are calculated via a base unit and fixed factors.
TemperatureSource temperature -> Celsius -> Target temperature
Temperature uses Celsius as an intermediate value so that offset and factor remain visible.
Knowledge
Why the calculator converts via base units
A shared intermediate base makes conversions consistent and the step-by-step solution transparent.
For length, weight and volume, a factor to the base unit suffices. The calculator therefore first converts to metre, kilogram or litre and then divides by the target factor.
Temperature is not a linear quantity value. Celsius, Fahrenheit and Kelvin have different zero points, so the conversion requires its own formula.
Length: base metre
Weight: base kilogram
Volume: base litre
Temperature: intermediate Celsius
Practice
Practical examples
For illustration only – your own calculation is what counts.
Length in everyday life
Convert metres to centimetres or kilometres to metres, for example for distance, room or material.
Result: 2.5 m equals 250 cm.
Weight in cooking
Kilograms, grams and milligrams can be quickly compared when quantity specifications are noted differently.
Result: 1.25 kg equals 1,250 g.
Understanding temperature
Celsius, Fahrenheit and Kelvin are converted with a dedicated formula, not just a factor.
Result: 20 °C equals 68 °F.
Volume for recipes
Litres, millilitres, cubic metres, teaspoons and tablespoons help with household, kitchen and simple quantity questions.
Result: 0.75 l equals 750 ml.
Notes
Common mistakes
Confusing prefixes (mega vs. milli)
Mega (M, factor 10^6) and milli (m, factor 10^-3) are confused. A megabyte is one million bytes, a millimetre is one thousandth of a metre.
Uppercase prefixes stand for large factors (k=1000, M=million, G=billion). Lowercase prefixes stand for small factors (m=thousandth, µ=millionth, n=billionth).
Converting temperature with a simple factor
Users multiply Celsius by a factor to get Fahrenheit. This gives wrong values because Fahrenheit has a different zero point.
Celsius to Fahrenheit: °F = °C x 9/5 + 32. The addition of 32 is necessary because 0 °C = 32 °F. Without the offset term, the result is incorrect.
Converting volume units linearly
1 metre = 100 centimetres, so it is assumed: 1 cubic metre = 100 cubic centimetres. In fact, 1 m³ = 1,000,000 cm³.
For volume, length factors are cubed: 100³ = 1,000,000. The calculator uses litre as the base unit, which avoids this error source.
Confusing German Pfund and Anglo-American pound
The German 'Pfund' (500 g) is equated with the Anglo-American pound (453.592 g). For larger quantities, the deviation adds up.
In an international context, always check which pound is meant. The calculator uses the international pound (lb = 453.592 g).
FAQ
Frequently asked questions
Which units are included?
The calculator includes core units for length, weight, temperature and volume. These include metre, kilometre, inch, foot, gram, kilogram, pound, ounce, Celsius, Fahrenheit, Kelvin, litre, millilitre, cubic metre, teaspoon and tablespoon.
Why does temperature have a different calculation method?
Temperature units are not converted using just a factor. Fahrenheit and Kelvin also need an offset, so the calculator shows its own intermediate steps.
Can I enter German decimal numbers?
Yes. Values like 1,5 or 1.000,5 are read as German decimal numbers.
Which unit is the intermediate base?
Length is converted via metre, weight via kilogram, volume via litre and temperature via Celsius.
Why are some results rounded?
The calculator shows clearly formatted numbers. Internally, conversions are calculated with the stored factors; for very long decimal values, the display is smoothed.
Can I enter negative values?
For length, weight and volume, negative values are not supported. For temperature, negative Celsius or Fahrenheit values are possible as long as they are not below absolute zero.
Why are there different pound definitions?
The German Pfund (500 g) and the Anglo-American pound (453.592 g) are historically different definitions. The calculator uses the Anglo-American pound (lb) as it is more common internationally. For the German Pfund, simply enter 0.5 kg.
How accurate are the conversion factors?
For SI units (metre, kilogram, litre), the factors are exactly defined. For Anglo-American units (inch, pound, gallon), the internationally agreed definitions apply (e.g. 1 inch = 25.4 mm exactly). Temperature conversions use the physically exact formulas.
Limits
Limitations
The calculator covers length, weight, temperature and volume. Area, speed, pressure and electrical quantities are not included.
Currency conversions are not included since exchange rates are date-dependent.
Temperature values below absolute zero (-273.15 °C / 0 K) are not accepted as they are physically impossible.
The display rounds to a readable number of digits. The internal calculation uses the full precision of the stored factors.
Sources
Sources and references
Internationales Einheitensystem (SI)Bureau International des Poids et Mesures (BIPM)
The SI defines the seven base units (metre, kilogram, second, ampere, kelvin, mole, candela) and their derivatives. Foundation of all metric conversions.
View sourceRetrieved: 06/15/2025 · Verified on: 07/22/2026
DIN 1301 – EinheitenDeutsches Institut für Normung (DIN)
German standard for naming, defining and writing units and unit prefixes. Governs the use of SI units in the German-speaking region.
View sourceRetrieved: 06/15/2025 · Verified on: 07/22/2026
Einheiten und MetrologiePhysikalisch-Technische Bundesanstalt (PTB)
The PTB is Germany's national metrology authority and realises the SI units. It provides reference values and conversion factors.
View sourceRetrieved: 06/15/2025 · Verified on: 07/22/2026
NIST Guide for the Use of the International System of UnitsNational Institute of Standards and Technology (NIST)
Reference work for converting between SI units and Anglo-American units (inch, pound, Fahrenheit). Contains exact conversion factors.
View sourceRetrieved: 06/15/2025 · Verified on: 07/22/2026
After a conversion, differences are often compared as percentages.
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