Rounding Calculator
Round a number to a given number of decimal places or to the nearest ten, hundred or thousand.
Last updated · View algorithm, constants and default inputs (JSON)
About this calculator
Rounding replaces a number with the closest value at a given precision. Standard rounding sends a five up, while bankers rounding sends it to the nearest even digit to avoid systematic bias. Exact half-way values are rounded away from zero (for example, −1.5 becomes −2).
Worked example
calculated with the default values below
Number 1,234.5678 · Decimal places 2 Rounded 1,234.570000 · Nearest ten 1,230.00 · Nearest hundred 1,200.00 · Nearest thousand 1,000.00 · Difference 0.002200
General background references
Disclaimer
These calculators give general mathematical results. They suit study, planning and estimation — verify anything that feeds a graded submission, a published figure or a financial commitment.
Implementation source
This record describes the implementation used by this page. It is not independent validation. External references, when available, support only the stated formula or definition; estimates and custom rules retain their own assumptions.
Formula and variables
R = round(V × 10^d) ÷ 10^d; R_k = round(V ÷ 10^k) × 10^k, k = 1,2,3
- V
- Value to round
- d
- Decimal places
- R
- Rounded value
- k
- Power: 1 tens, 2 hundreds, 3 thousands
Exact halfway values round away from zero.
Frequently asked questions
How are halfway values rounded?
Exact half-way values are rounded away from zero. For example, 1.5 rounds to 2 and −1.5 rounds to −2.