TOOL · ETF & COMPOUNDING

See what your monthly contributions become in 10–30 years

Model long-term ETF investing — inflation-adjusted real returns, contribution totals, and the curve of compound growth. Set your scenario, get a clear answer.

Try it yourself

Adjust monthly contribution, horizon, expected return and inflation. The chart and KPIs update live.

Top brokers for ETF investing

Ranked by objective trust score — the same methodology as our reviews

Interactive Brokers

SEC/FCA · 10.0

$0.005 · min $1Open account ↗

XTB

FCA/KNF · 10.0

Free ≤€100,000/mo · then 0.2% · min £10Open account ↗

eToro

FCA/CySEC · 10.0

FreeOpen account ↗

How the calculation works

Compound monthly

Each month your contribution joins the existing balance and earns return on the whole pot — interest on interest.

Inflation-adjusted

We compute both nominal and real (today's money) values. Real return tells you what your nest egg actually buys.

No magic numbers

Default return rates come from long-run global equity averages. Lower them for conservatism — never trust 12%+ promises.

Frequently Asked Questions

What return rate should I use?

The default 8% reflects the historical average annual return of global stock ETFs (e.g., S&P 500). For bond ETFs, 4–5% is more realistic. Past performance does not guarantee future results.

How does inflation adjustment work?

The calculator shows both nominal and real (inflation-adjusted) returns. Real returns subtract your specified inflation rate using compound math, giving you purchasing power in today's money.

Is compound interest really that powerful?

Yes. With monthly contributions of $300 at 8% annual return over 20 years, you contribute $72,000 but end up with roughly $176,000. The extra $104,000 comes from compound growth.

Does the calculator include broker fees?

No. This calculator focuses on investment growth. Use our Fee Calculator to estimate broker costs, then subtract that from your expected returns for a complete picture.

What ETFs should I invest in?

Common choices for beginners include broad market ETFs tracking the S&P 500 or All-World indices. Use our Portfolio Builder tool to get specific ETF suggestions based on your risk tolerance.

Find a broker that fits your ETF plan

BrokerFit's wizard matches you with brokers based on your country, deposit size, instruments and account currency — in under a minute.

Find my broker →

Affiliate disclosure

We may earn a commission if you open an account through our links. It does not change broker conditions and does not affect our ranking. Methodology →

Risk warning

Financial instruments carry the risk of capital loss. 74–89% of retail investors lose money trading CFDs. Assess whether you can afford this risk.

TOOL · ETF & COMPOUNDING

See what your monthly contributions become in 10–30 years

Model long-term ETF investing — inflation-adjusted real returns, contribution totals, and the curve of compound growth. Set your scenario, get a clear answer.

Try it yourself

Adjust monthly contribution, horizon, expected return and inflation. The chart and KPIs update live.

Inputs

Monthly contribution ($)$500/mo

Investment horizon20 years

Expected return (%/year)8%/year

Inflation (%/year)3%/year

Did you know

Did you know? Every year you delay investing $500/month costs you thousands in lost compound growth.

Open Cost of Delay calculator →

Final amount$294.5KNominal · 8%/year

Inflation-adjusted$163.1KReal purchasing power

Total contributed$120K$500 × 240 months

Portfolio growth · 20 years

Nominal vs inflation-adjusted

Nominal

Real value

This calculation is for illustrative purposes only. Past returns do not guarantee future results.

Top brokers for ETF investing

Ranked by objective trust score — the same methodology as our reviews

Interactive Brokers

SEC/FCA · 10.0

$0.005 · min $1Open account ↗

XTB

FCA/KNF · 10.0

Free ≤€100,000/mo · then 0.2% · min £10Open account ↗

eToro

FCA/CySEC · 10.0

FreeOpen account ↗

How the calculation works

Compound monthly

Each month your contribution joins the existing balance and earns return on the whole pot — interest on interest.

Inflation-adjusted

We compute both nominal and real (today's money) values. Real return tells you what your nest egg actually buys.

No magic numbers

Default return rates come from long-run global equity averages. Lower them for conservatism — never trust 12%+ promises.

Frequently Asked Questions

What return rate should I use?

The default 8% reflects the historical average annual return of global stock ETFs (e.g., S&P 500). For bond ETFs, 4–5% is more realistic. Past performance does not guarantee future results.

How does inflation adjustment work?

The calculator shows both nominal and real (inflation-adjusted) returns. Real returns subtract your specified inflation rate using compound math, giving you purchasing power in today's money.

Is compound interest really that powerful?

Yes. With monthly contributions of $300 at 8% annual return over 20 years, you contribute $72,000 but end up with roughly $176,000. The extra $104,000 comes from compound growth.

Does the calculator include broker fees?

No. This calculator focuses on investment growth. Use our Fee Calculator to estimate broker costs, then subtract that from your expected returns for a complete picture.

What ETFs should I invest in?

Common choices for beginners include broad market ETFs tracking the S&P 500 or All-World indices. Use our Portfolio Builder tool to get specific ETF suggestions based on your risk tolerance.

Find a broker that fits your ETF plan

BrokerFit's wizard matches you with brokers based on your country, deposit size, instruments and account currency — in under a minute.

Find my broker →

Affiliate disclosure

We may earn a commission if you open an account through our links. It does not change broker conditions and does not affect our ranking. Methodology →

Risk warning

Financial instruments carry the risk of capital loss. 74–89% of retail investors lose money trading CFDs. Assess whether you can afford this risk.

Inputs

Monthly contribution ($)$500/mo

Investment horizon20 years

Expected return (%/year)8%/year

Inflation (%/year)3%/year

Did you know

Did you know? Every year you delay investing $500/month costs you thousands in lost compound growth.

Open Cost of Delay calculator →

Final amount$294.5KNominal · 8%/year

Inflation-adjusted$163.1KReal purchasing power

Total contributed$120K$500 × 240 months

Portfolio growth · 20 years

Nominal vs inflation-adjusted

Nominal

Real value

This calculation is for illustrative purposes only. Past returns do not guarantee future results.