Baby Number Two Calculator

This calculator estimates the extra cost of having a second child in New Zealand, on top of what you already spend on your first, so you can budget realistically before the new baby arrives. Because much of the big one-off gear, the cot, pram, car seat and baby clothes, can often be reused, a second child is usually cheaper to start with than the first, even though costs that scale per child keep rising as your family grows. You enter your extra weekly spending on childcare, on food and nappies, and on other extras such as clothing or activities, plus any new gear you still need to buy rather than reuse. The calculator adds the weekly figures to show your extra cost per week, multiplies that by 52 for the extra cost per year, and adds the one-off gear spend to give a first-year total, typically the most expensive year since it carries both the new purchases and a full year of higher running costs. Use it to plan your budget around parental leave, decide whether you need a bigger car or house, or check whether your income and any Working for Families support will stretch far enough. Because this shows the gross added cost before extra support, and childcare usually falls once your child starts school, treat the figures as an indicative planning estimate rather than an exact forecast.

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$
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$0
extra per week for the second child
Extra per year$0
One-off gear$0
First year total$0

This is the gross added cost; Working for Families and other support can offset part of it, so check your entitlements. Childcare usually drops once the child starts school. Estimate only.

How it works

The calculator adds your extra weekly costs for childcare, food and nappies, and other items to give the ongoing extra per week, then scales it to a year. It adds the one-off gear you need to buy new to show a first-year total, which is usually the most expensive year. Because much of the big gear is reused from the first child, the second child often costs less to start than the first did.

Worked example

Extra costs of $220 childcare, $60 food and nappies and $30 other are $310 a week, about $16,120 a year. Add $1,500 of new gear and the first year is around $17,620. Once childcare reduces as the child grows, the ongoing cost falls considerably.

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