四捨五入計算機

共有リンク

はじめに

Rounding Calculator — Round a number to a chosen number of decimal places. Enter Number, Decimal places to get an instant, accurate result.

計算式

Rounds a number to the specified number of decimal places using standard rounding, and also reports the floor (round down) and ceiling (round up) values.

ステップごとの説明

Enter the Number.
Enter the Decimal places.
Click Calculate to see your result instantly.

実例

Example: With Number = 3.1416, Decimal places = 2, the Rounding Calculator gives Rounded: 3.14, Floor: 3, Ceil: 4.

よくある質問

How does rounding to 0 decimal places work?

It rounds to the nearest whole number.

What is the difference between the rounded value and floor/ceiling?

Floor always rounds down and ceiling always rounds up, regardless of the digit that follows, while the rounded value uses standard round-half-up behavior.

What inputs does the Rounding Calculator need?

You'll need to provide: Number, Decimal places. All fields use sensible defaults, so you can see a working example immediately and then adjust the values to match your own numbers.

How accurate is the Rounding Calculator?

The Rounding Calculator applies the formula exactly as calculated — Rounds a number to the specified number of decimal places using standard rounding, and also reports the floor (round down) and ceiling (round up) values. — so results are precise for the inputs you provide. Accuracy depends on entering correct, realistic input values.

Is the Rounding Calculator free to use?

Yes, the Rounding Calculator is completely free, requires no signup, and runs instantly in your browser.