Rounding Numbers Calculator

This online calculator provides two easy-to-use tools: Decimal Rounding Calculator and Integer Rounding Calculator. The decimal rounding tool lets you quickly round numbers to the desired number of decimal places, while the integer rounding tool allows you to round whole numbers to the nearest tens, hundreds, thousands, or other place values.

Standard Rounding and Other Rounding Methods

Most rounding calculators use the standard rounding method (Round Half Up). This is the same approach taught in schools:

If the digit after the rounding place is less than 5, round down.

If it is 5 or greater, round up.
Examples: 2.4 → 2; 2.5 → 3; -2.4 → 2; -2.5 → −2

Other Rounding Methods

Besides the standard approach, there are several alternative rounding modes used in finance, statistics, and programming:

Round Half Down - .5 values round down instead of up (2.5 → 2, -2.5 → -3). Used in some statistical calculations to reduce bias toward larger numbers.

Round Half Even (Banker’s Rounding) - .5 rounds to the nearest even integer (2.5 → 2, 3.5 → 4, −2.5 → -2). Common in finance and computer systems to minimize cumulative rounding errors.

Ceiling (Round Up) - always rounds toward positive infinity (-3.2 → −3, 3.2 → 4). Useful in billing and pricing when partial amounts must always be charged as full units.

Floor (Round Down) - always rounds toward negative infinity (-3.2 → -4, 3.2 → 3). Often applied in time tracking or inventory management when you cannot exceed limits.

Round Toward Zero (Truncation) - simply removes the decimal part without rounding (3.9 → 3, -3.9 → -3). Used in programming and integer division.