Ballpark Daily

Ballpark, played at ballparkdaily.com (not to be confused with the company-guessing game of the same name), asks five questions a day whose answers are numbers nobody knows exactly: how many milligrams of sodium are in a teaspoon of salt, how far the Moon is from Earth, or what a Tyrannosaurus rex skeleton sold for at auction. Each day's set is numbered, began with #1 on 20 September 2026, and the same five go to every player. Each question comes with a photo from Wikimedia Commons, credited on the picture.

You answer with a range. Drag the two handles on a logarithmic slider, where each tick to the right is ten times bigger, or type a low and a high value. Before you lock it in, the game shows how wide the range is and how many points it is worth if it holds the answer: up to 100 for a razor-thin range, down to 5 for a huge one. A miss scores nothing, so the skill is to go as narrow as you dare and no narrower.

After each question the answer appears on the slider beside your range, with a sentence of context and a link to the published source it comes from. At the end you get a score out of 500, your streak, and a calibration figure: the share of your ranges that contained the answer. The game says a good forecaster catches about four answers in five. You can share the result, download a scorecard image, send a friend a challenge link with your score, and see how your day compares with other players.

Past puzzles are in an archive and yesterday's answers, with sources, have their own page. Archive games do not touch your streak or calibration. There are no accounts: your streak lives in your browser, and the game can be installed as an app and send a daily reminder if you ask it to.

It suits players who like Fermi questions and want to practise being confident without being wrong.