A free daily size guessing game that trains your sense of scale.

Size It Up is a free browser game about real-world scale. Each daily puzzle presents five objects to compare with familiar references drawn at true scale. Resize the mystery silhouette, lock in your estimate, then reveal the actual measurement and its source. Play the same daily challenge as everyone else, explore unlimited practice across 12 categories, and switch between metric and US units. Scores reward accurate proportions, making each quick round a way to sharpen your intuition about the size of animals, landmarks, vehicles, space objects, and more.