Ziguva

Estimate everyday quantities and see 👀 how close your guesses land.

Ziguva trains your sense of scale. Each question asks for a real-world quantity, such as how many times a heart beats in a year 🗓️ or how many bricks are in the walls of a house. You make your best guess and see 👀 how close you came.

Answer in the way that suits the question:
• Single number 🔢: drag ✋ the slider or type ⌨️ a value.
• Factor chain: build 🔨 your answer from a few labelled numbers 🔢 that you multiply or divide, and watch 👀 the running product update.
• Low-high range: set a low and a high value, then choose how sure you are, from 70% to 95%.

After every answer you see 👀 the real figure, your points, and one sound route 🧭 to it. Tap 👆 any step in that route to save 💾 it as an anchor.

Today 📆's five is a fixed set of five questions each day, with a streak 🔥. Practice 🏋️ lets you pick a pack of questions, such as Everyday Scale, Body & Lifetime, Earth & Sky, Machines & Materials, Food 🍎 & Farming or Signals & Numbers. You choose the round length and the difficulty, or let the app pick the difficulty from your recent accuracy. When a round ends, a summary lists every answer with its score. You can then retry the questions you missed.

Ziguva keeps a library 📚 of anchors: short numbers 🔢 you want to remember, like minutes in a day. Star the ones you use most, borrow common ones from a built-in list 📋, or add your own.

The Calibration tab compares how sure you said you were with how often your ranges held the real figure. It shows whether you are overconfident or underconfident, how wide your ranges are, and how your error ❌ changes over time ⏱️.

Spend a few minutes a day with Ziguva and your quick estimates get sharper.