Rounding Calculator

Round numbers using different methods: standard, up, down, banker's rounding, and significant figures.

Original Number

3.14159265359

Rounded to 2 decimal places

3.14

Rounded to 4 significant figures

3.142

All Rounding Methods

Round Half Up

3.14

Floor (Round Down)

3.14

Ceiling (Round Up)

3.15

Truncate

3.14

Common Rounding Places

To Integer3
To Tenths (0.1)3.1
To Hundredths (0.01)3.14
To Thousandths (0.001)3.142

Rounding Error

Absolute Error

1.5927e-3

Relative Error

0.050696%

What is Rounding?

Rounding replaces a number with a simpler value that's approximately equal. It's used when precision isn't needed or when simplifying calculations.

Rounding Methods

Standard: 5 rounds up. Banker's: 5 rounds to nearest even, reducing cumulative bias. Ceiling/Floor: always up/down.

Significant Figures

Significant figures indicate the precision of a measurement. They include all certain digits plus the first uncertain digit. Leading zeros are not significant.