RealCost is a daily estimation game about the price of things — from a 1924 Ford Model T to a Salvator Mundi auction bid. Every puzzle has three rounds pulled from real, documented historical prices.

Your score for each question is an error ratio: how many times too high or too low your guess was compared to the real number. Your day score is the geometric mean of all three — so being consistently close beats nailing one and badly missing the other two.

A perfect day scores 1.00×. The lower your multiplier, the sharper your intuition.

This prototype contains a curated seven-day edition that repeats weekly. Comparison charts are simulated, not real player statistics.

New puzzles unlock day by day through the week — but you can always go back and play a day you missed. Your first completed run of any Daily is official and never changes; you can replay any unlocked day for fun without affecting your score, streak or stats.

RealCost does not collect, store, or transmit any personal data.

Your scores and progress are saved only in your browser's local storage, on your device. Nothing is sent to a server, and no account is required.

Clearing your browser's site data will permanently erase your history.