Category
Miscellaneous
Five odds and ends that are genuinely useful. Draw a random number in a range, roll any dice combination, flip a coin, convert to and from Roman numerals, or move a number between binary, hex, decimal, and octal.
All Miscellaneous tools5 tools
Randomness that is actually random
Random Number Generator, Coin Flip, and Dice Roller all draw from crypto.getRandomValues, the browser's cryptographically secure source, rather than Math.random. For picking a raffle winner or settling an argument the difference is academic, but it costs nothing and it means a coin flip is a genuine fifty-fifty rather than the output of a predictable sequence. The dice roller accepts standard notation, so 4d6 rolls four six-sided dice and reports the total along with each individual die.
Converting between notations
Roman Numeral Converter works in both directions and covers the standard range up to 3,999, which is where classical notation stops. Binary / Hex Converter moves a value between binary, hexadecimal, decimal, and octal in one view, so you can see all four at once rather than converting twice. It tolerates the usual prefixes and grouping, so 0x1F and 1010 1010 both parse.
Frequently asked questions
Is the random number generator genuinely random?
It uses crypto.getRandomValues, the browser's cryptographically secure random source, rather than Math.random. That gives each outcome an equal chance and makes the sequence unpredictable, which is stronger than these uses strictly require.
What dice notation is supported?
Standard notation such as 4d6, meaning four six-sided dice. D4, D6, D8, D10, D12, and D20 are all available, and the result shows each individual die alongside the total.
Why do Roman numerals stop at 3,999?
Classical Roman notation has no symbol above M for a thousand, so the largest value expressible with the standard letters is MMMCMXCIX, or 3,999. Larger numbers need an overline convention that was never consistently used.