Investment Calculator

Investment calculator 2026 online. Calculate your investment returns after taking into account deposits, fees, taxes and inflation

This tool simulates the development of an investment over time using compound interest. The calculator allows you to take into account the initial payment, monthly payments, rate of return, management fees, capital gains tax, inflation and the increase in payments in subsequent years. Thanks to this, you can realistically see how much you will actually earn and how much will be eaten up by costs and taxes.

Why it is worth using an investment calculator

Most people know the idea of ​​compound interest, but few can calculate the real effect in practice. All you need to do is add a management fee, inflation or tax for the final result to differ from the funds' advertising promises. The investment calculator allows you to take into account all these elements and estimate:

• final value of the investment,
• gross and net profit after tax,
• real value of capital after inflation,
• total amount of payments and actual profit over capital.

How to use the calculator

1. Enterinitial deposit, e.g. PLN 10,000.
2. Addmonthly payment, e.g. PLN 500.
3. Specify thenumber of years of investment(from 1 to 60).
4. Enter the averageannual rate of return, e.g. 7%.
5. Optionally, completemanagement fee, increase in annual payments, taxandinflation.
6. Select the capitalization method (monthly, quarterly or annual).
7. Click "Calculate" to see the results.

Calculation algorithm

The calculator simulates financial flows according to the following principles:

• Capitalization: profit added in accordance with the selected period (month, quarter, year).
• Deposits: added cyclically, taking into account the annual percentage increase (if specified).
• Fees: reduces the annual rate of return by the indicated percentage.
• Tax: charged on profits at the end of the investment.
• Inflation: real final value = nominal value / (1 + inflation)^years.

Step-by-step examples

Example 1: 10 years, PLN 500 per month, 7% per year

Initially PLN 10,000 + PLN 500 per month for 120 months. Nominally, you will get approximately PLN 103,000. Net profit (net of tax) ≈ PLN 33,000 over contributions.

Example 2: 20 years, PLN 500 per month, 7% per year, 1% fee

The fee lowers the effective rate to 6%. Final value ≈ PLN 247,000, which is several dozen thousand less than without fees.

Example 3: 30 years, PLN 500 per month, 7% per year, inflation 3%

The nominal result is ≈ PLN 566,000. After taking into account inflation, the real value drops to ≈ PLN 235,000. The difference shows the strength of long-term inflation.

Indicative table (example for PLN 500 per month, 7% per year, 0% inflation)

FAQ

Is the result certain?

No, this is a simulation based on the assumed rate of return. Financial markets are volatile.

Does the calculator take into account Belka's tax?

Yes, you can enter its amount (e.g. 19%). It is deducted from the final profit.

Can I change my deposits over time?

Yes, you can specify a percentage increase per year, such as a 5% increase in your monthly payment each year.

Does inflation always lower the score?

Yes, inflation reduces the real purchasing power of money. The calculator shows both values ​​- nominal and real.

Practical tips

• Always include fees and taxes - they have a big impact on the result.
• Think in terms of real value, not just nominal value.
• Treat the calculator as an educational tool, not as investment advice.
• Longer horizon = greater impact of compound interest.

Most common mistakes

• Assuming an unrealistically high rate of return.
• Ignoring inflation in simulations.
• Failure to include fees that always occur in practice.

Safety and responsible use

Recalculate your investment now