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Free tools

Calculators built for the NZ tax system.

No spreadsheets required. These tools handle the mechanics so you can focus on the decisions.

Tax calculator

FIF Tax Calculator

Compare FDR, Comparative Value and Cost Method side by side. Check whether you're above the $50,000 threshold and find your lowest legal FIF income for 2025–26.

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Rate finder

PIR / PIE Fund Calculator

Find your correct Prescribed Investor Rate for KiwiSaver and PIE funds. Using the wrong PIR means a year-end tax bill — or permanently overpaying. Takes about 60 seconds.

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Fee comparison

KiwiSaver Fee Comparison

See what management fees actually cost you over 10, 20 and 30 years. Small percentage differences compound into large dollar amounts — this tool makes that visible.

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Platform comparison

Platform Fee Comparison

Find the cheapest NZ investing platform for your portfolio size and contribution amount. Compares Sharesies, Hatch, InvestNow and Kernel side by side — including the 5-year cost difference.

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These tools back up the writing

Each calculator is built around a topic covered in The Southern Portfolio newsletter. Read the articles for the context, use the tools to run your own numbers.

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One issue a week on investing from New Zealand — the context behind the numbers.

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