Example 1
- Total: 100
- Ratio: 3 : 2
60 · 40
Five parts of 20 - three for the first side, two for the second.
Divide an amount in a ratio calculator
Type the whole and two ratio parts. 100 in 3 : 2 splits into 60 and 40, five parts of 20. 90 in 1 : 2 is 30 and 60. Parts are non-negative and not both zero.
The amount can be any number - dollars, kilograms, or points. Both ratio parts must be non-negative and cannot both be zero.
Result
Enter the total and ratio a : b.
How does it work?
Treat the whole as a sum of (a + b) equal parts. The first side gets a of those parts, the second gets b. Formulas: share 1 = whole × a ÷ (a + b), share 2 = whole × b ÷ (a + b). 100 × 3 ÷ 5 = 60, 100 × 2 ÷ 5 = 40. The shares add back to 100.
90 in 1 : 2: three parts, one is 30, two are 60. The whole can be money, mass, or points. The ratio parts must be non-negative and cannot both be zero.
Fields: Amount to split, First ratio part, Second ratio part. Type 100, 3, and 2, click Calculate. A comma and a period both parse. Check that 60 + 40 = 100.
Reducing 12 : 8 to 3 : 2 lives on ratio of two numbers. The rule of three hunts a missing x; it does not slice one whole. GCD(3, 2) = 1, so 3 : 2 is already short.
Without the whole or both parts, nothing computes. 100, 3, and 2 still give 60 and 40 no matter the header currency.
200 in 1 : 1 is 100 and 100. 50 in 2 : 3 is 20 and 30. 120 in 5 : 1 is 100 and 20.
Formula
share 1 = total × a ÷ (a + b)
share 2 = total × b ÷ (a + b)
How to use
- Type the amount to split, for example 100.
- Type the first ratio part, for example 3.
- Type the second ratio part, for example 2.
- Click Calculate. 100 in 3 : 2 gives 60 and 40. 90 in 1 : 2 gives 30 and 60.
- Reducing 12 : 8 lives on ratio of two numbers. A fourth unknown lives on the rule of three.
100 in 3 : 2 is 60 and 40
Split in a ratio: 100 in 3 : 2 is 60 and 40. 90 in 1 : 2 is 30 and 60. 120 in 5 : 1 is 100 and 20.
- 3 : 2
- The ratio. Five parts. From 100 you get 60 and 40. From 90 in 1 : 2 you get 30 and 60.
- whole
- The amount to slice. 100, 90 or 120. The shares add back to this number.
Examples
Example 2
- Total: 90
- Ratio: 1 : 2
30 · 60
One third and two thirds of the whole.
Example 3
- Total: 50
- Ratio: 4 : 1
40 · 10
Four fifths and one fifth - e.g. splitting a prize.
Example 4
- Total: 120.5
- Ratio: 2 : 3
48.2 · 72.3
The total need not be a whole number - the ratio of parts matters.
Example 5
- Amount to split: 90
- First ratio part: 1
- Second ratio part: 1
45 · 45
Does a 1:1 split of 90 give 45 and 45? Yes. Two equal parts of 45.
Related calculators
Frequently asked questions
How do I split 100 in the ratio 3 : 2?
60 and 40. Five parts of 20: three for the first side, two for the second.
How do I split 90 in 1 : 2?
30 and 60. One third and two thirds of the whole. Three parts of 30.
What is the formula?
Share 1 = whole × a ÷ (a + b). Share 2 = whole × b ÷ (a + b). The sum returns to the whole.
Must 60 + 40 equal 100?
Yes. If the sum drifts, check the a and b you typed. The calculator keeps the parts adding to the whole.
What are 200 in 1 : 1 and 50 in 2 : 3?
200 in 1 : 1 is 100 and 100. 50 in 2 : 3 is 20 and 30. Five parts of 10 on the second split.
Can the parts be zero?
One can be 0, both at once cannot. 100 in 1 : 0 gives the whole to the first side.
How is this different from reducing 12 : 8?
There you get 3 : 2. Here you already have 3 : 2 and you slice 100 into 60 and 40.
Must the whole be an integer?
No. 10.5 in 1 : 2 still splits. Keep the ratio parts non-negative.
What is 120 in 5 : 1?
100 and 20. Six parts of 20: five for the first side, one for the second.
Is 15% of 200 this split?
No. 15% of 200 = 30 lives on percentage of a number. Here you slice a whole in a given ratio.
Knowledge sources
The calculator computes the same formula as the definition below.
Page updated in 2026.