Calculator
Example Data Table
| Input | Target | Method | Rounded Output |
|---|---|---|---|
| 1234.5678 | 2 decimal places | Half up | 1234.57 |
| 0.004567 | 2 significant figures | Half up | 0.0046 |
| 9876.5 | Nearest hundred | Half even | 9900 |
| -42.58 | Nearest tenth | Floor | -42.6 |
| 58 | Nearest multiple of 7 | Half up | 56 |
| 465 | Nearest ten | Half down | 460 |
Formula Used
General formula:
rounded = R(x ÷ step) × step
x is the input number, step is the rounding gap, and R is the selected rounding rule.
- Decimal places: step = 10-d
- Significant figures: step = 10floor(log10(|x|)) - s + 1
- Place value: step equals the selected place value, such as 10 or 0.01
- Nearest multiple: step equals the chosen multiple
How to Use This Calculator
- Enter the number you want to round.
- Select whether you want decimal places, significant figures, a place value, or a multiple.
- Choose the rounding rule that matches your maths task.
- Enter the needed precision or multiple.
- Press Calculate Rounding to view the result, step details, graph, and export buttons.
FAQs
1. What is standard rounding?
Standard rounding usually means half up. Digits below 5 stay the same. Digits 5 or above raise the previous kept digit by one.
2. What are significant figures?
Significant figures count meaningful digits from the first non-zero digit. They are useful when you want precision based on value scale rather than fixed decimal places.
3. What is banker’s rounding?
Banker’s rounding sends exact .5 ties to the nearest even result. It helps reduce bias when many rounded values are added together.
4. How does rounding work for negative numbers?
Negative values follow the same selected rule, but direction matters. Ceiling moves upward, floor moves downward, and truncate moves toward zero.
5. What is the difference between place value and decimal places?
Place value targets named positions such as tens or hundredths. Decimal places count digits to the right of the decimal point.
6. Can I round to the nearest multiple?
Yes. Enter the number, choose nearest multiple, and provide the multiple. The calculator scales the value, rounds it, then rescales it.
7. What do the CSV and PDF downloads include?
They include the current result summary, including the input, rounded output, method, step size, and other calculated details shown in the result table.
8. Why is a graph useful for rounding?
The graph helps compare the original number, rounded value, and difference. This makes the rounding effect easier to see at a glance.