Pattern Lab
Test your luck
Five symbols, one hidden card. Can you do better than chance?
Each card is one of five symbols, drawn at random for every card, so every guess has a 1 in 5 chance. Here, luck means chance: by chance alone, a run of 25 cards scores 5 on average.
The game
Before you guess, our server draws the card with a cryptographic random number and sends your page only its fingerprint: a SHA-256 hash of the run, the card's number, its symbol and a random secret. After your guess it reveals the symbol and the secret, and your page works out the hash again. If they match, the card was fixed before you chose; nobody, us included, could change it after seeing your guess.
Your progress
Sign up to save your progress. There's no password: we email you a link to sign in.
Accounts are for people aged 16 and over. Your email address is used only to send you sign-in links and is never shown to anyone: you play under a name we make up for you. See the privacy policy and the Pattern Lab terms.
Signed in as .
Settings
Names are made up from our own word lists, so nothing anyone types is ever shown to others.
A file with your account and every run, card by card.
This deletes your account, with your email address and your name, at once and for good. It can't be undone. It also turns off your space weather alerts, on this device and on the devices where you've been signed in; alerts work without an account, so you can turn them on again. Your runs stay in the all-players results, anonymously: nothing in them links to you any more.
You play one run a day: today's run. more
Start it when you like. Once it starts, you have an hour to finish it (signed in, on this page or any device where you're signed in); cards not played by then count as misses, so nobody can keep just their good runs. Play it before you sign up and it's saved to your new account. With 30 days of runs (750 guesses), random guessing keeps a hit rate between 17% and 23% 95 times in 100, so a real difference would have room to show.
All players so far
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Leaderboard
Only players who switched on a public profile. Places say what happened in their runs, with how often chance alone does the same.
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How it works
Every guess has a 1 in 5 chance. more
Each card is drawn at random, so whatever you do, each guess hits 1 time in 5. That's why we know exactly what random guessing gives.
Each run notes 10 conditions. more
Geomagnetic activity (Kp), the Sun's magnetic field at Earth (Bz), the solar wind's speed and density, the Sun's X-rays, the Moon (waxing or waning, near full or not), Mercury retrograde, the time of day and the day of the week where you are (from your device's time zone).
Ten checks look for a difference. more
Each check needs 10 runs on each side. It only says "unusual" when a difference is bigger than chance usually makes, even allowing for ten checks; "no difference" is shown just as plainly. Mercury and the Moon are here because people ask about them, not because we expect them to matter.
Your results unlock after 30 days. more
With an account, today's run counts each day. 30 days (750 guesses) is enough to show a big difference: a true 25% hit rate shows up 95 times in 100. Titles say what happened: Ace 9+ hits in a run (random guessing does this 1 in 21 runs), Expert 10+ (1 in 58), Superstar 12+ (1 in 650), Legend 15+ (1 in 74,000), Perfect 25; Regular, Researcher and Veteran for 7, 30 and 100 days.
Every guess counts. more
Everyone's results use every guess in runs played without an account, finished or not (no IP address, nothing that identifies you), and in each signed-in player's run of the day ("today's run"), which stays in, anonymously, if an account is deleted. Each guess is 1 in 5 whenever anyone stops, so stopping a bad run can't lift the results. They're worked out once a day. See the privacy policy.