CATEGORY
Math & Number Calculators
Number systems, base conversions, and printable reference charts — binary, hex, octal, and decimal with every formula shown and every answer exact.
Math
Average time
Total, mean, fastest, and slowest from a list of times.
Open calculator →MathSignificant figures
Count sig figs and round to N — with the rules explained.
Open calculator →MathHex to RGB converter
Decode any hex color, with CSS snippets and a live preview.
Open converter →MathBinary, hex & decimal chart
Convert 0–255 between binary, hex, octal, and decimal — plus the full 256-row ASCII reference chart.
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