How the scratch card works
Type anything you like into the list, one outcome per line, and press new card. The moment the card is made, your browser's cryptographic random number generator (crypto.getRandomValues, the same machinery used to create encryption keys) draws one line and prints it under a layer of virtual foil. Then the fun part: rub the foil away with your finger, stylus or mouse, exactly as you would with a coin on the real thing. The outcome is fixed before you touch the card, so where you scratch, how fast you scratch and which corner you start in make no difference at all.
Once about 60% of the foil has gone, the card clears the rest itself, because by then the answer is showing anyway. Everything runs in your browser: your list of outcomes is never uploaded, nothing is stored, and refreshing the page starts you fresh. If your device is set to reduce motion, the final reveal skips the fade and clears instantly.
Working out the odds
Every line gets an equal chance, which makes the odds easy to reason about and easy to rig, in the nicest possible way. Repeat a line to make it more likely; keep every line unique for a fair draw.
Fun ways to use it
- Family prize draws: load it with small treats and one dud, then hand the phone round after dinner and let everyone scratch their own.
- Reveals: put the announcement on every line, from a holiday destination to good news you have been sitting on, and let someone scratch their way to it.
- Chore roulette: list the week's jobs and scratch one per person. Somehow losing to a scratch card stings less than being told.
- Classrooms and quizzes: reveal team names, bonus points or forfeit tasks with a bit more drama than reading them off a list.
- Deciding anything: dinner options, film choices, who goes first. If you would have flipped a coin, you can scratch a card instead.
A toy, not a gambling product
This page borrows the satisfying part of a scratch card, the rubbing and the reveal, and none of the rest. Nothing is staked, nothing is paid out, and you write every outcome yourself, so there are no hidden odds and no house edge. Real scratch cards are gambling: the odds are set so the operator keeps a margin, the big prizes are deliberately rare, and in the UK you must be 18 to buy one. If you or someone you know is finding real gambling hard to keep fun, free and confidential support is available at gambleaware.org. Here, the worst you can lose is the last biscuit.
Frequently asked questions
When is the outcome decided?
The moment a new card is made, before you scratch anything. Your browser's cryptographic random number generator picks one line from your list and hides it under the foil. Scratching only reveals what is already there, so where and how you scratch makes no difference.
Can I change the odds of an outcome?
Yes. Every line gets an equal chance, so repeat a line to weight it. If your list has four lines and one of them appears twice, that outcome has a 2 in 5 chance. Most real prize draws work best with lots of try again lines and one rare winner.
Why did the card finish revealing itself?
Once you have scratched away about 60% of the foil, the card clears the rest for you. That matches how people use real scratch cards: by that point the answer is obvious, and the auto reveal saves your finger the last few rubs.
Does it work on phones and tablets?
Yes. The foil responds to any pointer, so you can scratch with a finger, a stylus, a mouse or a trackpad. Everything runs in your browser and your list of outcomes never leaves your device.
Is this gambling?
No. It is a toy. Nothing is staked, nothing is paid out, and you write every outcome yourself, so there are no hidden odds. Real scratch cards are a form of gambling with a house edge and an age limit of 18 in the UK, which is a different thing entirely.