To miscalculate means to figure something out incorrectly, usually by making a mistake in math or judgment. When you miscalculate how much time you need for homework and end up rushing through the last problems, you've made an error in your planning. When a baker miscalculates the amount of flour needed and the cake doesn't rise properly, they've gotten their measurements wrong.

You can miscalculate simple things, like misjudging how many cookies will fit on a baking sheet, or complex things, like a general who miscalculates the enemy's strength before a battle.

Sometimes people miscalculate because they're careless, but sometimes they just don't have all the information they need. A hiker might miscalculate how long a trail will take because they didn't account for steep hills. An architect who miscalculates the weight a beam can support can create a dangerous situation.

The consequences of miscalculating depend on what's at stake. Miscalculating your allowance might mean waiting another week for that game you want. Miscalculating a rocket's trajectory could mean missing Mars entirely. That's why engineers, pilots, and scientists check their calculations multiple times before acting on them.