To round a number to the nearest 100, look at the tens digit. If it is 0, 1, 2, 3 or 4, round down: keep the hundreds digit and change the tens and ones to 0. If it is 5, 6, 7, 8 or 9, round up: add 1 to the hundreds digit and change the tens and ones to 0. So 748 rounds to 700 and 750 rounds to 800.
Reviewed by the Helping with Math Team · Updated 10 October 2026
In order to ease our calculations, we often approximate the numbers to some extent. It helps us give approximate answers where exact values are not required. For instance, we may say that there are around 600 students in a school. That does not necessarily mean that there are exactly 600 students in a school. The exact number of students in the school may be somewhere around 600 which, for convenience we have rounded to 600.
So, how do we decide how to round off a number to the nearest 100?
Before understanding the rules to round off a number, it is important to understand what does rounding off to 100 mean?
It means we find the multiple of 100 that is closest to the number. The tens and ones digits become 0.
Rounding up vs rounding down
Rounding Up
If the digit at the hundreds place is followed by 5, 6, 7, 8 or 9, the number is rounded up.
Example – We want to round off 54897 to the nearest 100.
1. Look for the digit at the hundred’s place. It is 8.
2. Now look for the digit to the right of the digit at the hundred’s place. The number is 9
3. Since 9 is 5 or more, we round up to the next hundred: the hundreds digit 8 becomes 9 and the tens and ones become 0.
Hence, the number 54897 after being rounded off to the nearest 100 is 54900
Note : Here we moved up the number to the nearest hundred, which is why it is called rounding up.
Let us take another example.
Example – We want to round off 71367 to the nearest 100.
1. Look for the digit at the hundred’s place. It is 3.
2. Now look for the digit to the right of the digit at the hundred’s place. The number is 6
3. Since 6 is 5 or more, we round up to the next hundred: the hundreds digit 3 becomes 4 and the tens and ones become 0.
Hence, the number 71367 after being rounded off to the nearest 100 is 71400
Rounding Down
If the digit at the hundreds place is followed by 0, 1, 2, 3 or 4, the number is rounded down.
Example – We want to round off 24615 to the nearest 100.
1. Look for the digit at the hundred’s place. It is 6.
2. Now look for the digit to the right of the digit at the hundred’s place. The number is 1.
3. Since this number is less than 5, we round down the number, so we keep the hundreds digit 6 and change the tens and ones to 0.
Hence, the number 24615 after being rounded off to the nearest 100 is 24600.
Note : Here we moved down the number to the nearest hundred, which is why it is called rounding down.
Let us consider another example
Example – We want to round off 4738 to the nearest 100.
1. Look for the digit at the hundred’s place. It is 7.
2. Now look for the digit to the right of the digit at the hundred’s place. The number is 3.
3. Since this number is less than 5, we round down the number, so we keep the hundreds digit 7 and change the tens and ones to 0.
Hence, the number 4738 after being rounded off to the nearest 100 is 4700.
Rounding to the nearest 100 on a number line
Rounding off to the nearest 100 can also be understood graphically as shown below
First it should be understood that when you are rounding off to the nearest 100, the digit at the hundred’s place needs to be looked into.
Let us take a number 748
This number lies between 700 and 800. To round off this number, either we take it back to 700 or move it forward to 800. How do we decide where to go?
Look at the number line below:
Numbers in the lower half are rounded down to 700 and numbers in the upper half are rounded up to 800. This is because the numbers from 700 to 749 are closer to 700 as compared to 800. Hence they will be rounded down.
However, the numbers that lie between 750 and 799 are closer to 800 due to which they would be rounded up to 800.
The rule to remember
When rounding off a number to the nearest hundred, look at the TENS DIGIT of the number.
- If that digit is 0, 1, 2, 3, or 4, you will round down to the previous hundred. (Round down)
- If that digit is 5, 6, 7, 8, or 9, you will round up to the next hundred. (Round Up)
More examples of rounding to the nearest 100
Let us round off these numbers to the nearest 100
| Number | Tens digit | Nearest 100 |
|---|---|---|
| 6,216 | 1 (round down) | 6,200 |
| 845 | 4 (round down) | 800 |
| 9,562 | 6 (round up) | 9,600 |
| 10,160 | 6 (round up) | 10,200 |
| 601 | 0 (round down) | 600 |
| 4,945 | 4 (round down) | 4,900 |
| 2,264 | 6 (round up) | 2,300 |
| 1,419 | 1 (round down) | 1,400 |
| 22,366 | 6 (round up) | 22,400 |
| 14,158 | 5 (round up) | 14,200 |
A graphical representation of rounding off to the nearest 100 has been presented below for better understanding.
Think of how many students are at your school. Unless it is a small school you would probably think of a number to the nearest hundred. Below are three examples of rounding an exact number to the nearest hundred.
Note: You can use this rounding calculator at the foot of this page to round a number to the nearest 100.
Rule for rounding to the nearest 100
- Tens digit 0, 1, 2, 3 or 4Round down: keep the hundreds digit.423 → 400
- Tens digit 5, 6, 7, 8 or 9Round up: add 1 to the hundreds digit.881 → 900
Look at the number in the tens’ place and…
View the examples below showing how to round to the nearest 100
Example 1
Example 2
Example 3
How to round to the nearest 100
- 441Tens digit 4: round down to 400
- 178Tens digit 7: round up to 200
- 922Tens digit 2: round down to 900
- 4568Tens digit 6: round up to 4,600
Rounding Calculator
748: the tens digit is 4, so round down. 748 rounded to the nearest 100 is 700.
More Rounding Help
To the nearest 10 To the nearest 1000 Larger numbers With decimals
More practice: rounding whole numbers worksheets, rounding whole numbers and decimals worksheets and rounding whole numbers to the nearest tens and hundreds worksheets.
Rounding to the nearest 100 FAQs
How do you round to the nearest 100?
Look at the tens digit. 0 to 4: round down (keep the hundreds digit). 5 to 9: round up (add 1 to the hundreds digit). Then make the tens and ones 0.
What is 450 rounded to the nearest 100?
500. The tens digit is 5, so you round up, even though 450 is exactly halfway between 400 and 500.
What is 950 rounded to the nearest hundred?
1,000. Rounding up from 9 hundreds carries into the thousands place.
What is 49 rounded to the nearest 100?
0. 49 is closer to 0 than to 100, because its tens digit is 4.
Which digit do you look at to round to the nearest hundred?
The tens digit, the one just to the right of the hundreds place. The ones digit does not matter: 449 rounds to 400.
What is the difference between rounding to the nearest 10 and the nearest 100?
For the nearest 10 you look at the ones digit; for the nearest 100 you look at the tens digit. 1,267 rounds to 1,270 (nearest 10) and 1,300 (nearest 100).
