Compound growth assumptions: returns, fees, timing

The calculator is only as good as the assumptions you feed it. Here is how to set them in a way that is useful for real planning rather than wishful thinking.

Quick answer: The most important drivers are time, contribution size, and fees. Use a realistic average return and a low/high band to explore range, not certainty.

Return assumptions: think long-term averages

Use a steady average return rather than a single great year. If you are unsure, pick a base return and then set a band around it to see how sensitive the result is. The goal is not to predict the market, but to understand what your plan needs to work.

Fees: include the all-in cost

Enter the total annual fee you actually pay (fund fee plus platform or account fee). A small percentage compounds against you every year, so it is worth being realistic instead of optimistic.

Contribution timing: start or end of month

If your saving happens right after payday, the start-of-month setting may be a closer fit. If you typically move money at month end, choose end-of-month. The difference is small per month, but it adds up over many years.

Inflation: what the money is worth later

The inflation toggle shows values in today's SEK so you can compare future goals to current prices. It is a simple way to keep expectations grounded when you are planning for long horizons.

Use the uncertainty band as a stress test

The low and high lines are not predictions. They are a way to stress-test your plan if returns are better or worse than your base assumption. If a goal only works in the high case, it may need a backup plan.

Assumptions: Constant average return, periodic contributions, and fees applied evenly. Taxes and account rules are not included.

Use the calculators

Set your base return, band, fees, and inflation toggle to see how sensitive the outcome is.