Coin flip.

Yes. Each flip is one bit from crypto.getRandomValues, the browser's cryptographic generator, so heads and tails are exactly as likely. Earlier flips don't change the next one.

Runs are more common than they feel: in 100 flips the longest run of one side is usually around 7. The tally shows the run to expect for the number of flips, about log2 of the count plus a third, beside the one you got.

Their shares get closer to 50% as the flips add up, but the counts rarely match. In 10 flips a 7 to 3 split or wider happens about a third of the time; after 10,000 the share is usually within a percent of half.

Choose 5, 10 or 100 under Coins and press Flip. Every coin of the toss is shown, and the status line counts its heads and tails.

For the session, up to 100,000 flips: the tallies cover them all and the strip shows the last 60, newest first. Copy takes them as a line of H and T; Reset clears them, and nothing is kept when you close the tab.

No. The coins are flipped in your browser and the page makes no request.

No. The "Coin flip" tool is free and opens without a sign-in, an account or an install.

1, 5, 10 or 100 a press. A session keeps up to 100,000 flips for its tallies, and the strip shows the last 60.

The session's flips in order, as one line of H and T, ready to paste into a spreadsheet or a note.

The page opens on an example session from a fixed seed so it isn't empty, and the status line says so. Your first press of Flip starts a session of your own.

Closest to the "Coin flip" tool: Dice roller, Random number generator, Random string generator, Timer and stopwatch. Each opens on its own page, free and in the browser.

The "Coin flip" tool is one of 20 in its group. The group's page, /tools/math, lists them all.

The tool is free. Its interface is built from shadcn.io's own components (Button, Input, Slider and the rest of the registry under /ui), which come in React, Vue, Svelte and Solid. Pro adds the blocks and templates for the product around it.