Rounding Calculator

Look at the digit after your rounding position. If it is 5 or greater, round up. If it is less than 5, round down (keep the digit). Example: rounding 3.456 to 2 decimal places — look at the third decimal (6). Since 6 >= 5, round up: 3.46. The calculator applies this rule consistently and shows the decision at each step.

Round half up: 2.5 rounds to 3 (always round up on .5). Round half even (banker's rounding): 2.5 rounds to 2, 3.5 rounds to 4 — always round to the nearest even number. Banker's rounding reduces cumulative bias in large data sets. The calculator supports both methods.

Select the rounding place: nearest ten means the ones digit decides (round 345 to 350, round 342 to 340). Nearest hundred means the tens digit decides (round 345 to 300, round 350 to 400). The same principle applies to any place value — the calculator handles all of them.

Yes — significant figures rounding keeps a specified number of meaningful digits. 0.004567 to 3 significant figures = 0.00457 (leading zeros are not significant). 12345 to 3 significant figures = 12300. This type of rounding is standard in science and engineering for reporting measurement precision.

Rounding considers the next digit and may increase the last kept digit (3.456 rounds to 3.46). Truncating simply cuts off digits without considering them (3.456 truncates to 3.45). Truncating always rounds toward zero, while rounding can go either direction. The calculator offers both options.