Savings goal calculator

What this calculation means

• Separate money already available from future contributions. B is the month-end balance, C the beginning-of-month contribution, and P all contributed principal including starting capital. Exclude emergency cash and money needed soon.
• The monthly rate is the nominal annual return r minus annual fees f, divided by 12. Tax t and inflation i are editable assumptions. Defaults of 0% do not promise a return or establish tax exemption.
• A is the balance after hypothetical tax on positive cumulative gains. R is that balance in today’s purchasing power; m counts months. The target compares A or R depending on the selected basis.

Formula and calculation order

B_m = (B_(m-1) + C) × (1 + (r − f) / 1200); A_m = B_m − max(B_m − P_m, 0) × t / 100; R_m = A_m / (1 + i / 100)^(m / 12)

1. Add the contribution at the beginning of each month, then apply the monthly rate. The annual input is a nominal rate, not an effective annual yield.
2. At each observation, apply tax once to positive cumulative gains. Tax is not withdrawn every month from the compounding balance.
3. Search up to 1,200 months for the first target crossing. Binary search finds the minimum whole-KRW monthly contribution that meets the deadline.

Worked examples

Costs and conditions to check

• Subtracting annual fees from returns is a simplified model. Trading costs, currency conversion, performance fees, account-specific taxes and allowances are excluded.
• Actual returns fluctuate and losses are possible. A fixed-rate path is neither a probability estimate nor a capital guarantee.
• Reserve money for annual bills and emergencies before committing monthly savings. A negative budget capacity should be resolved before increasing contributions.

Questions for each scenario

• For variable income, start with an amount you can maintain in a low-income month. Treat additional income separately.
• A target expressed in today’s purchasing power requires a larger future nominal balance when inflation is positive. Choose the target basis first.

The effect of a one-point annual fee

Start at zero, target KRW 100 million in 60 months, contribute KRW 1 million monthly, and assume 5% annual returns. Only fees change; tax and inflation are zero.

The 5% return is an illustration. Check product-specific fees and taxation separately.

Extending the deadline by one year

Start at zero with a KRW 100 million target and KRW 1 million monthly contributions. All rates are zero; only the deadline changes.

Arrival depends on current contributions, so changing the deadline does not change arrival. It changes the required monthly contribution.

Adding KRW 100,000 a month

Start at zero, target KRW 100 million in 60 months, and set all rates to zero. Only the actual monthly contribution changes.

The required contribution uses the same 60-month deadline. Increasing actual contributions shortens arrival time.

Common mistakes

• Do not include inaccessible housing equity or pension assets as available starting cash.
• Do not raise the assumed return merely to make a difficult target look achievable. Adjust contributions or the deadline against your budget first.

Questions to consider

Official educational references

• The SEC tools explain savings goals using initial capital, monthly contributions, time and returns. This page’s fee, tax and inflation extensions follow the simplified assumptions above; they do not determine any jurisdiction’s tax treatment.