Rule of 72 vs CAGR Calculator: Which Is the Right Shortcut?

Why this page exists

Compare mental shortcut and exact annualized calculation.

Reader job: At 6%, Rule of 72 estimates about 12 years to double; exact compounding gives about 11.9 years.

Target: Human reader usefulness

Real evidence or example

St. Louis Fed explains the Rule of 72; calculator math is reproducible.

This page does not use fabricated private claims. It is grounded in public source material, local GSC evidence, or reproducible calculations.

Human-first example and decision

At 6%, Rule of 72 estimates about 12 years to double; exact compounding gives about 11.9 years.

The example is intentionally limited to public sources, local GSC evidence, or reproducible arithmetic. It does not invent a private customer story.

How to use this page

• Start with the page's direct answer.
• Check the cited source, local signal, calculator, or policy before acting.
• Use the related homepage/tool if the decision depends on user-specific inputs.

Success metric

Page earns GSC impressions or assists an existing homepage/query cluster within 14-30 days.

Keep or revise rule

Keep if it earns impressions, supports a live signal cluster, or improves internal routing; revise or merge if it stays undiscovered after indexing and internal-link checks.

Sources checked

• St. Louis Fed compound interest explainer
• Federal Reserve Education simple and compound interest lesson