The length converter converts millimeters, centimeters, meters, kilometers, inches, feet, yards, and miles. It uses exact international definitions for imperial units and a single meter-based conversion path.
How to use this calculator
Enter a value, choose its source unit, and select the target unit. Negative values are accepted for mathematical consistency even though physical lengths are usually nonnegative.
Formula & calculation method
Meters = input × source factor; output = meters / target factorOne inch is exactly 0.0254 meters, one foot exactly 0.3048 meters, one yard exactly 0.9144 meters, and one international mile exactly 1,609.344 meters. Metric factors are powers of ten.
Worked example
One meter equals 100 centimeters and approximately 3.28084 feet. One mile equals exactly 1.609344 kilometers. The display rounds only the final result, not intermediate conversion factors.
Why this is useful
Using meters as a common base prevents inconsistent direct-factor tables and makes every pair follow the same logic. A broad unit set supports study, travel, shopping, craft, and measurement tasks.
Limitations to keep in mind
The converter addresses length only, not area, volume, or specialized surveying units. Very large or small values inherit ordinary floating-point display limits, and measurement uncertainty is not calculated.
Frequently asked questions
Are inch and foot conversions exact?
Yes. The international inch is defined as exactly 25.4 millimeters and the foot as exactly 12 inches.
Can I convert negative values?
Yes mathematically. This can be useful for coordinate differences, although a physical length itself is normally nonnegative.
Does this convert square units?
No. Area conversion requires squared factors and should be handled separately.