The 1–2 range
Two options, one answer. A 1–2 draw is the plainest decision machine there is: label one option 1, the other 2, and hand the choice to something with no opinion.
It is a coin flip without the coin, which turns out to matter. A tossed coin is a physical object with a wobble, and physics gives it a faint memory of how it started. Software has no such tell.
Draw once for a yes or a no. Draw ten times if you want to see what a fair fifty-fifty really looks like, streaks and all.
- 1 to 2, both included
- 2 whole numbers
- 50%, exactly 1 in 2
- 1 to 10 numbers per draw
- None up to 2 numbers, then unavoidable
- Every draw gets a link that replays it
What a 1–2 draw is for
- Deciding who serves, breaks or goes first
- Splitting a group into two teams, one draw per person
- Choosing between two restaurants when nobody will commit
- Assigning A or B while running a small test by hand
- Settling a two-way tie with no coin in your pocket
How the randomness works
Every tap calls crypto.getRandomValues, the browser's cryptographic generator, and asks it for one unsigned 32-bit value. That lands somewhere between 0 and 4,294,967,295, and it then has to be folded down to the 2 numbers in this range.
Folding it down is where most generators quietly go wrong, though not on this range. 2 is a power of two, so it divides 4,294,967,296 exactly and no raw value is ever awkward. The rejection step is still in the code; on 1–2 it simply never fires, and a plain remainder would give the same flat 50%, because modulo bias cannot arise on a power of two.
Ask for more than one number and the tool keeps drawing until it holds that many distinct values, then sorts them ascending. Nothing is seeded, nothing is sent anywhere, and each draw is independent of the one before it. The roll history under the tool lives in your browser's local storage, where the clear button empties it. The daily lucky numbers elsewhere on this site work the opposite way on purpose: they use a seeded generator so the same date always returns the same set. How random is random sets the two side by side.
Two divides the 32-bit draw space exactly, so nothing here is ever discarded. This is the one family of ranges where the careless method and the careful one agree, and the fifty-fifty is exact to the last decimal. A real coin is not: a 2023 study of 350,757 tosses found coins land on the face they started on about 50.8 percent of the time.
- crypto.getRandomValues, the browser's cryptographic generator
- One unsigned 32-bit value, sometimes more
- Rejection sampling onto 2 slots
- None: 2 divides 4,294,967,296 exactly
- No. These tools are never seeded
- Your browser. No server ever sees a draw
1–2 — frequently asked
Whichever you say before you draw. Announcing it afterwards is how arguments start.
Marginally, and for a reason worth knowing. A flipped coin precesses as it spins, so it spends slightly more time showing the face it started on, and a large 2023 experiment measured that at 50.8 percent. Nobody is winning money off a 0.8 percent edge, but the draw here has no such lean at all.
Tap three times and take the majority. It does not make the underlying draw any fairer, it only makes the outcome feel less arbitrary. If you want a coin with a running heads-and-tails tally, the coin flip tool keeps one.