Clear tools for long-term investors.

Compound Years is a free set of calculators and guides for long-term ETF investors. It helps you estimate growth, compare funds, understand fees and tax, and plan goals like financial independence — with every assumption visible and editable, and no sign-up.

Yes. Every calculator and guide is free, works in your browser and needs no account. You can share any result by copying the link, which saves your inputs.

Nobody knows future returns. Broad stock-market ETFs have historically delivered positive returns over long periods, but with large swings along the way and long stretches of poor results. Our calculators use round, editable planning assumptions — such as 7–8% a year before inflation for stock funds — and always show lower and higher scenarios so you can see a range rather than one number.

An index fund tracks a market index such as the S&P 500. An ETF (exchange-traded fund) is a fund that trades on a stock exchange like a share. Most popular ETFs are index funds, so the terms overlap: an index ETF is both.

A global ETF such as VWRA spreads your money across thousands of companies in developed and emerging markets. An S&P 500 ETF such as CSPX or VOO holds the 500 largest US companies, which already make up over 60% of a global fund. Global is the more diversified default; S&P 500 is a deliberate tilt toward the US.

They are funds legally based in Ireland, such as CSPX and VWRA. Under the US–Ireland tax treaty, US dividends paid to these funds are generally taxed at 15%, compared with a 30% default for non-US investors holding US-domiciled funds without a treaty. They are also generally outside US estate tax. Our Withholding Tax Calculator shows what that means in money.

Accumulating ETFs reinvest dividends inside the fund; distributing ETFs pay them to you. If dividends are taxed when paid where you live, accumulating usually grows faster. If you want regular income, distributing can suit you better. Some countries tax both types the same way, so check your local rules.

More than most people expect. Fees are taken from your whole balance every year, so their cost grows with your money. On a long-term monthly plan, the difference between a 1% and a 0.07% yearly fee can reach tens of thousands. The ETF Fee Calculator shows the exact figure for your plan.

Historically, investing a lump sum straight away has come out ahead more often, because markets have risen more often than they've fallen. Spreading it out over several months reduces the regret of investing just before a fall, at some expected cost. Our Lump Sum vs Monthly calculator lets you test both, including a market drop.

Start from your goal and timeline, then work backwards. For example, at an assumed 7% a year, $300 a month for 30 years could grow to about $365,991 — while the same amount for 20 years reaches about $156,278. The How Much to Invest Monthly calculator solves this for any target.

It's the amount you would need invested for your portfolio to cover your yearly spending — usually your annual spending divided by a safe withdrawal rate. At 4%, that's 25 times your yearly spending. The FIRE Calculator shows your number and how long it could take to reach it.

No. Compound Years provides educational tools and general information only. Results are estimates based on the assumptions you enter, not predictions or recommendations. For decisions about your own money, tax or circumstances, consider speaking with a qualified professional.