Free tools to help you model your mortgage, tax, KiwiSaver, and more
Numbers make better decisions. The tools below are all free, independent, and built specifically for New Zealand's tax and financial system — covering everything from your take-home pay to your KiwiSaver balance at retirement. None of these calculators require you to create an account or share personal information beyond what you enter.
These calculators are provided by government agencies, regulated financial advice firms, and independent organisations. They are not financial advice — but they are a useful starting point before you speak with a qualified adviser.
Enter your hourly, weekly, or annual salary and see exactly what you take home after PAYE income tax, ACC levy, KiwiSaver contributions, and student loan deductions. Supports secondary income, payroll giving, holiday pay, and salary sacrifice arrangements — with results across hourly, weekly, fortnightly, monthly, and annual timeframes.
Open calculatorEstimate how long your student loan will take to repay based on your current balance and income, and model the impact of making extra voluntary repayments. Accessed via myIR — the tool takes around five minutes and can be a powerful motivator for accelerating repayment.
Open calculatorWork out whether income you receive from boarders or home-stay students is taxable using the IRD's standard costs method. Enter your total gross income from the boarding arrangement, the number of boarders, and their length of stay — the calculator tells you whether you need to include this income in an IR3 return.
Open calculatorCalculate your weekly, fortnightly, or monthly mortgage repayments based on the loan amount, interest rate, and loan term. Useful for stress-testing your budget at different rate scenarios — particularly relevant as mortgage rates remain volatile and many New Zealanders are rolling off fixed-rate terms in 2026.
Open calculatorEstimate how a New Zealand investment property could grow in value over time. Enter the property purchase price and growth rate assumptions to model your projected equity position. A useful tool for investors comparing property returns against other asset classes over 5, 10, or 20-year time horizons.
Open calculatorThe RBNZ's official inflation calculator lets you compare the purchasing power of a dollar amount across any two years in New Zealand's history, drawing on CPI data since 1914. Useful for understanding how the cost of living has changed over time — and what today's prices mean in historical context.
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