Downloadable NZ Mortgage & Property Calculators

Every sheet below is a downloadable Excel calculator, the exact one our advisers use in client meetings. Pick one in the form above and it lands in your inbox in minutes. Here's what each one actually does and who it's for.

Calculators for homeowners

The sheets below do the maths; for the bigger picture, start with our home owner guide.

Usable Equity

Your paper equity and the equity a bank will let you borrow against are two different numbers. This sheet works out how much you can genuinely access for a top-up, renovation or your next purchase. Want an instant, address-based estimate instead? Run our usable equity report.

Offset or Revolving Credit

Both structures put your savings to work against the mortgage, but they suit different money habits. Compare offset against revolving credit on your actual balances and see the interest saved and the time cut from your loan with each.

Debt Consolidation

Rolling a car loan or credit cards into the mortgage usually drops your weekly outgoings, but it can stretch short debts over decades. This sheet shows both sides: the repayment relief now and the total interest over the full term.

One Income Survival

Planning for parental leave, a career change, or simply stress-testing the household? Map your budget on a single income and see how long savings hold the line, before it happens rather than after.

Calculators for property investors

Deep in the numbers? The property investor guide covers the strategy these sheets support.

Pay Down or Invest

Spare cash each month: extra mortgage repayments or invest it? This sheet puts the guaranteed return of paying down debt next to investing over your timeframe. It's the most requested calculator we have.

Equity to Your First Rental

Most first rentals in New Zealand are bought with equity, not savings. Work out how much usable equity your home holds, the deposit banks expect on an investment property, and the gap you'd need to close.

Minor Dwelling

A minor dwelling can add rent and value, or quietly eat the gain through build costs, consents and rates. Run the build cost, likely rent and extra lending against each other before you ring a builder.

Portfolio: Hold or Sell

When one property is dragging, the real question is which one, compared with what. Line up each property's cashflow, growth and equity so the hold-or-sell call is a comparison, not a gut feeling.

Investor Cashflow

What does a rental actually cost to hold each week once rates, insurance, management and maintenance join the mortgage? This sheet gives you the true weekly position, not the brochure yield.

Calculators for first home buyers

Buying your first place? The first home buyers guide walks the whole journey; these sheets handle the sums.

How Much Can I Borrow?

Bank calculators hand you a headline number; this sheet shows the working. Income, expenses and existing debts against the rates banks actually test you at, so you know your realistic price range before you fall for a listing. The current test settings live on our borrowing power page.

Joint Buyers Split

Buying with a partner, friends or family who've put in different amounts? Agree the ownership split, the repayment shares and what happens if someone wants out, on paper, before you sign anything.

Buy vs Rent

Renting isn't dead money and buying isn't automatically the win. Compare the true cost of each over the years you'd stay put, including the rates, insurance and maintenance that only sit on the buying side.

Can't pick one? Choose Send me the full library in the form and all 32 sheets arrive in a single email.

New: plug our live NZ lending data into your AI

We keep New Zealand's current lending numbers — bank test rates, DTI and LVR limits, living costs and more — reviewed every Monday on our borrowing-power page.

• Bookmark it: the always-current figures live at /borrowing-power/.
• Using ChatGPT or Claude? Add our free skill so your AI always pulls the latest numbers — download the skill.
• Developers & agents: grab the machine-readable JSON feed.