Divide in Ratio Calculator

Split any amount fairly according to any ratio you choose.

How it is calculated

Each share is the total times its ratio term, divided by the sum of all terms: shareX = total × partX ÷ (A + B + C). The third term C is optional: if you leave it empty or set it to 0, it counts as 0 and the total is split between A and B only, with Share C shown as 0.00. Ratio terms may be decimals such as 1.5 and 2.5. They cannot be negative, and at least one must be above zero. The total itself can be any number, including a negative one, in which case the shares are negative too. Each share is rounded to two decimals, so the displayed shares may add up to a cent more or less than the total. The ratio can be given in any scale: 2:3 and 4:6 give the same shares.

Worked example

Share 900 in the ratio 2:3:5. Sum of the terms: 2 + 3 + 5 = 10. Share A: 900 × 2 ÷ 10 = 180.00. Share B: 900 × 3 ÷ 10 = 270.00. Share C: 900 × 5 ÷ 10 = 450.00. Check: 180 + 270 + 450 = 900. The tool displays 180.00, 270.00 and 450.00 for A, B and C.

Try this example →

Common mistakes

  • Dividing the total by the number of parts and multiplying. For 2:3:5 each unit is 900 ÷ 10 = 90, not 900 ÷ 3.
  • Entering the ratio as percentages that do not sum to 100. That is allowed, since 20:30:50 and 2:3:5 are the same ratio, but 20:30:40 is a different split.
  • Putting a 0 for a part that should count. Part C of 0 drops the third share completely, so 1:1:0 is just 1:1.
  • Expecting rounded shares to add up exactly. Splitting 100 as 1:1:1 shows 33.33 three times, which sums to 99.99.
  • Putting the ratio in the wrong order. The first term matches Share A, so 2:3 and 3:2 swap the amounts.

About this calculator

Dividing a quantity in a given ratio, such as splitting 150 in the ratio 2:3, or 300 in the ratio 2:3:5, means partitioning it into parts whose sizes are proportional to the ratio terms: each part equals the total multiplied by its ratio term and divided by the sum of all ratio terms. For a two-part ratio a:b, the first share is total × a ÷ (a+b) and the second is total × b ÷ (a+b); a three-part ratio extends the same logic with a+b+c in the denominator.

This kind of proportional split shows up constantly outside the classroom: dividing profits between business partners according to their investment ratio, scaling ingredients in a recipe to a different ratio of components, apportioning an inheritance or shared cost among parties, or mixing chemical solutions, paints, or concrete in specified ratios.

Was this helpful?

You can pick up to 3 reactions.

Comments

  • Be the first to comment.

Popular calculators

All Calculators