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FIRE Guides

Understand the model before you trust the numbers.

Each guide explains a specific part of the FIRE calculator — the assumptions it makes, how comparison works, and how to stress-test your plan.

Foundations

Calculator Assumptions

Core ETF, property, tax, and spending assumptions inside the calculator. Start here to understand what the model does and doesn't cover.

8 min
Assumptions

Investment Assumptions

Set realistic ETF return, dividend, franking, property yield, vacancy, and expense assumptions when comparing investment paths.

8 min
Analysis

How to Stress-Test Your Plan

Use alternate scenarios and sensitivity analysis to test whether your plan still works when returns drop or costs rise.

6 min
Strategy

Staged Contributions

Model changing savings capacity over time — salary increases, family costs, debt payoff — instead of one flat number.

5 min

Ready to model your path?

Open Calculator

Last updated 29 March 2026 · Tax year 2026-27

Data sources: ATO: Tax rates for Australian residents

This tool is general information only, not financial advice.

Reviewed by AusTax Tools Editorial Desk

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