Irish Calculators
Saving & investing

Investment Scenario Comparison Calculator

Model two return and fee assumptions using the same starting balance and contribution schedule. The comparison excludes tax and does not rank real products or establish suitability.

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Your numbers

%
A scenario, including price growth where relevant.
%
Applied as a proportional reduction over each period.
%
Used only for purchasing-power values.
%
Use the same currency and horizon.
%
Percentage of balance.
Display currency only. Convert all inputs to this currency before calculation.
Your figures stay on this device.

How the calculation works

A comparison is useful only when the amount and timing of money invested are held constant. This calculator applies two sets of return and balance-fee assumptions to the same saving schedule, separating their projected outcomes from product selection.

Apply each scenario’s effective return and proportional fee to the same periodic balances, then compare final values.

  1. Set one common cash schedule

    Both scenarios begin with the same capital and receive the same contributions at the selected beginning or end of each period.

  2. Apply returns and fees separately

    Each scenario converts its annual effective return and annual balance charge into periodic growth and deductions. Fees affect future growth because the deducted money no longer remains invested.

  3. Compare the ending balances

    The difference subtracts scenario B from scenario A. Both nominal balances are also divided by the same cumulative inflation factor to express purchasing power.

Worked example: Check A minus B

Sample inputs demonstrate the method. They are not a forecast or product offer.

In the first example, both scenarios start at 1,000, grow at 10% for two years and have no deposits or fees. Their balances are identical, so A minus B is zero.

Starting balance
1000
Contribution per period
0
Annual effective growth rate (%)
10
Years
2
Periods per year
Annual
Contribution timing
End of each period
Annual balance fee (%)
0
Annual inflation (%)
0
Scenario B annual effective return (%)
10
Scenario B annual balance fee (%)
0
Currency for all amounts
Euro (EUR)

Expected result

A minus B
€0.00
Worked example: Check A minus B

Sample inputs demonstrate the method. They are not a forecast or product offer.

Starting balance
1000
Contribution per period
0
Annual effective growth rate (%)
0
Years
1
Periods per year
Annual
Contribution timing
End of each period
Annual balance fee (%)
0
Annual inflation (%)
0
Scenario B annual effective return (%)
0
Scenario B annual balance fee (%)
10
Currency for all amounts
Euro (EUR)

Expected result

A minus B
€100.00

Understanding your result

A positive difference means A has the larger projected balance under the supplied assumptions. It does not say that A has lower risk, better liquidity or stronger guarantees.

The fee figures describe this modelled charging pattern. They do not reproduce a provider's complete tariff, and no tax or historical performance data is added.

Questions you might have

What does the result include?

Compare two investment scenarios over the same horizon and contributions, with separate returns and balance fees.

Which limits should I check?

Tax and guarantees are not modelled. A higher projected value alone does not establish suitability.

Choosing the right inputs

Contribution per period
Enter the amount added each selected period. The form accepts non-negative contributions; it does not provide a withdrawal schedule.
Scenario B annual balance fee
This is an annual proportional charge on the balance. Do not include a charge here if you already removed the same charge from the return assumption.
Annual inflation
Use a common inflation assumption for both scenarios so their purchasing-power figures remain comparable.

Common mistakes to avoid

  • Do not compare a before-fee return in one scenario with an after-fee return in the other.
  • A larger forecast balance is not evidence that an actual investment will outperform.

Assumptions to check

  • Tax and guarantees are not modelled. A higher projected value alone does not establish suitability.
  • All calculations run on your device. Figures are scenarios based on your inputs, not investment recommendations.

Sources and method

Read our calculation and testing approach.