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Budget Rule Comparator

Enter your net monthly income and compare four popular budget rules side by side. See how much each rule would allocate to needs, lifestyle, savings, investing or giving.

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01

Your inputs

Takes ~ 1 minute
02

Your result

Fill in the fields above and click Calculate — your personalised plan appears here in a moment.

How to use the comparison

Budget rules are shortcuts. They help you see whether a plan is balanced before you build a detailed spreadsheet.

Which rule is best?

50/30/20 is a broad baseline. 70/20/10 leaves more room for living costs. 70/10/10/10 separates saving, investing and giving. 40/40/20 is aggressive and usually fits high-savings phases.

Plain-language notes

Use this section if the finance words on the page are new to you. The calculator is meant to support a decision, not to reward perfect terminology.

  • Budget rule: a starting split for income, not a law. Adjust it if rent, childcare, debt, or local prices make the rule unrealistic.

  • Budget category: a named bucket such as housing, food, transport, or savings. Clear buckets make leaks easier to spot.

What to compare

Compare at least two scenarios before trusting the first answer. A useful result should tell you what changes if income, costs, rates, or timing move.

Frequently asked questions

Which budget rule should I choose?
Start with the rule that fits your biggest constraint. High rent may need 70/20/10; aggressive saving may fit 40/40/20.
Are budget rules exact?
No. Use them as a first pass, then adapt for rent, debt, family support and variable income.

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