Costcodle

Costcodle puts a single Costco product on screen (photograph, full name, package size), and asks for its price. You get six guesses, entered as dollars in a field under the board, and each one comes back with a direction rather than a distance. A guess that is too high returns an orange down arrow, meaning the real shelf price sits below it. A link at the foot of the page credits the Costco Food Database the prices come from.

1. Read the product card carefully, the brand, the item and the package size all move the price.
2. Type a dollar amount into the field and press Submit.
3. Read the arrow: down means the real price is lower than your guess, up means higher.
4. Bisect the remaining range across your six guesses; the arrows are the only information you get.

It is a knowledge test disguised as a number game, and the knowledge is unusually specific: not what groceries cost, but what they cost at Costco, where bulk sizes bend every intuition you have from a normal supermarket. Thirty-two ounces of sliced cheese has no obvious price until you have stood in that aisle. The six-guess budget with pure higher-lower feedback makes it a clean binary search. The fun is in how few guesses your instinct actually saves you.

One signal, and it is directional. A wrong guess keeps its dollar figure on the board and adds an arrow beside it: down when the true price is lower, up when it is higher. There is no warmer-or-colder gradient, so a guess that misses by a dollar looks identical to one that misses by twenty, and the counter above the rows advances from Guess 1/6.

Daily product

One Costco item per day, shared by everyone, with a statistics panel behind the chart icon.

• Price the package, not the product. Costco sells in bulk, so the unit that matters is the 32-ounce pack rather than what a slice of cheese costs anywhere else.
• Open in the middle of a plausible range rather than at a guess you believe. With only arrows for feedback, a deliberate bisection wastes fewer turns than an accurate hunch followed by small steps.
• Watch the .99 convention: Costco prices cluster on specific endings, so once the arrows have bracketed you to a dollar, the cents are rarely a free choice.