RealCost is a daily price-guessing game. Make one guess for each of three questions, then discover the real prices and the stories behind them.

A new Daily arrives at 00:00 UTC, at the same moment worldwide. Visit Archive to play available earlier days or review your results.

Each round measures how many times your guess differs from the real price: the larger of your guess divided by the price and the price divided by your guess. A guess twice as high or half as high scores 2.00×. The scoring system treats an absolute difference below $0.0001 as an exact match.

Your final Daily score is the geometric mean of the three round multipliers: multiply them together and take the cube root. 1.00× is perfect; lower is better. Scores are displayed rounded, but calculated from the underlying values.

You have one official attempt per day and can resume an unfinished attempt. After completing a day, replay it for fun without changing your official result, progress or streak.

Playing the official game. RealCost connects to Supabase to create or restore an anonymous sign-in session. You do not need to enter a name or email to play, but your session has a persistent player identifier. Anonymous sign-in does not mean that no data is stored.

What is saved. The server stores your player identifier, Daily attempts and their dates and status, submitted guesses, question-version references, round and final scores, scoring version, timestamps and request identifiers used to prevent duplicate submissions. These records support resuming games, history, results and streaks.

On your device. Browser storage keeps the sign-in session, theme and sound preferences, and pending-answer retry information. The separate local version saves progress on your device. Clearing site data can remove access to your anonymous session; it does not delete records already saved on the server. A different browser, device or domain does not automatically share that session.

Player comparisons. Official answers and completed Daily scores contribute to aggregate comparison statistics. The statistics API returns grouped counts and comparisons, not other players' individual answer records. Replay does not submit new official answers or scores.

Service connections. The public site is hosted on Cloudflare Pages and uses Supabase for authentication and game data. Fonts are requested from Google Fonts, and images may load from their configured hosts. These services receive network information such as your IP address as part of handling requests. Their logging and retention settings are separate from the game's browser storage.

Sharing and external links. Copying a result places text or an image on your clipboard when supported; an image download may be offered if copying is unavailable. RealCost does not automatically post it to social media. Opening a source link takes you to another website.

There is currently no in-game control for deleting server-side history or transferring an anonymous session to another account.