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Coin flip

Two coins with draws 0, 1 are one heads and one tails. The count runs from 1 to 20.

Why this exists

A coin has two sides. Draw 0 lands on heads and draw 1 lands on tails, so neither side is favored.

The random-number page picks any integer range. This page only picks heads or tails.

  1. 01How to use it

    Enter a count from 1 to 20 and press flip.

    More than one coin also shows how many landed on each side.

    Copy puts one line such as Heads 1 · Tails 1 on the clipboard.

  2. 02What you get

    2 coins, draws 0, 1 are Heads 1 · Tails 1.

    1 coin, draw 1 is tails.

    3 coins, draws 1, 1, 0 are Heads 1 · Tails 2.

    Entered2 coins · 0, 1

    2 · 0, 1 Heads 1 · Tails 1
    1 · 1 Tails
    3 · 1, 1, 0 Heads 1 · Tails 2
    21 stops

  3. 03Worth knowing

    0 coins and 21 coins stop.

    Closing the tab clears the coins.

    Nothing is sent to a server.

Questions

QWhat do draws 0, 1 do?
AThey are one heads and one tails.
QWhat is draw 1 on one coin?
ATails.
QWhat about 21 coins?
AIt stops. The count runs from 1 to 20.
QIs this the random-number page?
ANo. This page only picks heads or tails.

How this page works it out

This page flips a coin to heads or tails. Draw 0 is heads and draw 1 is tails. Two coins with draws 0, 1 are one heads and one tails. More than one coin shows the count, such as Heads 1 · Tails 1. Three coins with draws 1, 1, 0 are Heads 1 · Tails 2.

The count runs from 1 to 20. Zero coins, 21 coins, and 1.5 stop. A draw is a 32-bit value. Two divides that range, so every draw is kept and both sides are equally likely. The random-number page can pick a range that does not start at 1. This page only picks the two sides.

The flip stays in this browser. Pressing the tray flips again. Closing the tab clears the coins. Nothing is sent to a server.

  • # coin
  • # heads
  • # tails
  • # flip