$25 a week invested for 30 years

Long time horizons make compounding powerful. Run a few return-rate scenarios and compare the range of outcomes.

Try the Money Growth Calculator

Why small amounts can become big numbers

Over 30 years, your time horizon often matters more than trying to find the “perfect” return. Compounding has decades to work.

Quick setup

  1. Convert $25/week to monthly: about $108/month ($25 × 52 ÷ 12).
  2. Years: 30
  3. Test 5%, 7%, and 10% return assumptions.

Try increasing contributions later

If $25/week is your starting point, test “step-ups” by increasing the monthly contribution every few years. Even small increases can move the result a lot.

FAQ

Is $25/week enough to bother?

It can be. The key is consistency and time. Over 30 years, even small contributions can compound into meaningful totals.

What return rate should I use?

Start conservative (5%), then compare with a mid-range assumption (7%) and an optimistic scenario (10%).

Weekly vs monthly — does it matter?

For long-term modelling, converting to a monthly number is usually close enough.

Does this include fees/tax?

No. Fees and taxes reduce real outcomes. Treat results as estimates.

Where can I learn the formula?

See /how-compound-interest-works.html for the simple explanation and formula.

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