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Business · Calculator

Rule of 40 Calculator

Calculate the simplified SaaS Rule of 40 sum.

Rule of 40 sum

43%

A simplified SaaS heuristic, not a universal valuation rule.

Formula: Rule of 40 adds revenue growth percentage and profit margin percentage.

Input policy: Growth and margin percentages may be negative. Count and money inputs elsewhere are kept non-negative.

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How to use this calculator

Calculate the simplified SaaS Rule of 40 sum.

How the calculation works

  • Enter the business inputs for the metric.
  • The calculator applies the displayed formula.
  • Review the result, assumptions, and related tools.

Formula

Rule of 40 = revenue growth percentage + profit margin percentage

Example

35% growth and 8% profit margin gives 43%.

Understanding your result

Use the output as a practical starting point, then review it before using it in an important workflow.

Assumptions and limitations

  • Simplified business planning math only.
  • This is not accounting, tax, legal, investment, or valuation advice.

Frequently asked questions

Does this require an account?

No. The core tool works without creating a Tool2Do account.

Is my input included in share links or analytics?

No. Tool2Do share actions use the tool page URL and safe metadata, not private values or uploaded files.

Rule of 40 Calculator | Tool2Do