Each category uses a canonical base unit. An entered number is converted to that base, then from the base into the requested destination unit. This avoids maintaining a separate, error-prone factor for every possible pair.
Non-linear units
Temperature is handled with affine formulas rather than a simple multiplier. Celsius and Fahrenheit are converted through kelvin so offsets remain correct.
Precision and rounding
Calculations use JavaScript’s double-precision arithmetic. We display roughly 10–12 meaningful digits, remove unnecessary trailing zeroes, and use scientific notation for extreme values. A rounded display value is never reused as the source of another calculation.
Standards
Definitions and exact relationships are based on recognized SI and NIST references. US customary and imperial liquid volumes are intentionally separate, as are decimal GB and binary GiB.
Limitations
Displayed results may be rounded. Do not use this general-purpose site where regulated calibration, safety-critical engineering, or professional certification requires specialized instruments or standards.