Calculators
Work through percentages and unit conversions accurately, including the common traps.
Percentages and units: the formulas, the bases, and the prefix conventions behind the numbers.
See all Calculators tools
- Calculating Percentage Change Correctly
Compute percent increase and decrease, and tell a percent change apart from a percentage-point difference.
- Percentage Points vs Percent
The difference between a change in percentage points and a percent change, with concrete examples.
- How to Convert Units Without Losing Precision
Convert length, mass, temperature, and data-size units while keeping the ratio, prefix, and precision straight.
- SI Decimal Prefixes and Binary Prefixes
Kilo, mega, and giga versus kibi, mebi, and gibi, and why a 1 TB drive reports less than 1 TiB.