Ratio Splitter Calculator NZ 2026

This calculator splits any amount into shares according to a ratio, which is one of those everyday maths jobs that is easy to get slightly wrong by hand. A ratio describes how something should be divided in proportion rather than equally, and it comes up constantly: splitting a bill or a prize between people who contributed different amounts, dividing profit between business partners, sharing rent by room size, mixing fuel, fertiliser, concrete or a recipe to a set proportion, or allocating a budget across categories. You simply enter the total amount and the ratio, written with colons such as 2:3:5 for three shares or 1:1 for an even split between two, and the calculator instantly returns each share. It handles any number of parts and any size of total, and works just as well for dollars as for litres, grams, hours or any quantity. The maths is straightforward but error-prone: you add up the ratio parts to get the total number of units, work out the value of one unit by dividing the amount by that total, then multiply each ratio part by the unit value. Doing it by hand invites mistakes, especially with three or more parts or awkward totals, and this tool removes that risk and shows the breakdown clearly. Use it to settle shared costs fairly, to scale a recipe or a mix up or down while keeping the proportions, or to divide anything that should not be split evenly. The shares always add back up to your original total. This is an exact calculation; just enter the ratio in the order you want the shares reported.

Calculate.co.nz is proud to be partnered with Premium Homes, a recognised leader in eco-friendly, sustainable, and energy-efficient homebuilding. With a dedicated team and award-winning experience, they create homes that prioritise health, comfort, and long-term performance. Their founders, Andrew and Kelly, set out to raise the standard of residential construction in New Zealand by combining practical building expertise with a clear commitment to doing things better for homeowners.
Premium Homes: got a section? Let's build your eco home on it.
Advertise on this page
$
-
share breakdown
Ratio total10
Per unit$100.00

Works for money or any quantity (litres, grams, hours). Shares always add back to the total. An exact calculation.

How it works

Add up the parts of the ratio to get the total number of units. Divide the amount by that total to get the value of one unit. Each share is then its ratio part multiplied by the unit value. The shares always sum back to the original amount.

Worked example

Splitting $1,000 by the ratio 2:3:5 gives 10 ratio units in total, so each unit is worth $100. The shares are 2 times $100, 3 times $100 and 5 times $100, which is $200, $300 and $500. They add back to $1,000. The same method scales a recipe or divides litres or hours.

Related calculators

Frequently asked questions

How do I split an amount by a ratio?

Add the ratio parts to get the total units, divide the amount by that to get the value of one unit, then multiply each part by the unit value. This calculator does it instantly for any ratio and total, with shares that always add back to the original amount.

Can I use more than two parts?

Yes. Enter as many parts as you like separated by colons, such as 2:3:5 or 1:1:1:1. The calculator handles any number of shares and reports them in the order you enter them.

Does it only work for money?

No. A ratio split works for any quantity: litres of a mix, grams in a recipe, hours of work, or a budget. Enter the total in whatever unit you are using and the shares come out in the same unit.