Random number generator
Nothing yet. Results appear here so you can prove what came up.
This generator draws whole numbers from a range you choose, using the browser’s cryptographic randomness with rejection sampling so that every value in the range is equally likely. Turn on "No repeats" to draw a set of distinct numbers — six from forty-nine, for instance — rather than independent draws that may collide.
How to use it
Most naive generators take a random 32-bit value and apply a modulus, which quietly favours the low end of any range that is not a power of two. This one rejects and redraws the small slice of values that would cause the bias, so a range of 1 to 6 is exactly uniform rather than nearly so. The difference is invisible in ten draws and measurable in ten thousand.
Questions
Yes. From 1 to 100 can produce 1 and can produce 100.
It draws without replacement, so you get distinct values. Asking for more numbers than the range holds returns the whole range, shuffled.
Yes, and the seed field is what makes it defensible. Announce the seed beforehand, and anyone can reproduce the draw afterwards.
Anything up to about nine quadrillion. Drawing five distinct numbers from a billion is instant, because the range is never materialised in memory.