Lifetime investing calculator

Money Seasons

A retirement calculator and investment growth calculator for the way investing actually happens: changing income, different contribution seasons, evolving stock and bond mixes, retirement withdrawals, historical returns, and future dollars translated into today's spending power. Start with small monthly investments in your 20s or 30s and see how time can do more of the heavy lifting.

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30-40 $500/mo Building the habit
40-50 $1,000/mo Peak earning years
50-65 $18k/yr Catch-up season
65+ 4% Retirement withdrawals

Why it is different

Regular calculators flatten your life. Money Seasons keeps the shape.

Contribution seasons

Most compound interest calculators assume the same monthly investment forever. This lets you model real stretches: early career, family years, higher income years, catch-up years, or time off.

Retirement is part of the plan

Keep investment returns running after retirement and test withdrawal rates instead of stopping the retirement calculator right when the most important questions start.

Stock, bond, and historical views

Compare stock-only, stock-and-bond, and historical return paths, including different stock and bond allocations before and after retirement.

Today's spending power

Toggle an inflation-adjusted view near the graph to see what future balances may feel like in today's dollars.

For young investors

See how early investing habits can grow into long-term freedom.

Start with what you can

Use the monthly investment calculator to test beginner-friendly amounts like $50, $100, or $250 a month and see how consistent investing may compound over decades.

Model raises and career growth

Young investors rarely save the same amount forever. Add contribution seasons for first jobs, promotions, side income, 401(k) increases, IRA contributions, or future catch-up years.

Learn risk and allocation

Compare stock-heavy growth assumptions with stock and bond mixes so you can understand how portfolio allocation may affect a long-term retirement savings plan.

Think beyond the headline number

Turn on today's-dollar results to estimate future spending power, because inflation matters when your investing timeline stretches from your 20s to retirement.

Why contribution seasons matter

Many investment calculators ask for one initial investment, one monthly contribution, one annual return, and one time period. That is useful for a quick compound interest estimate, but it does not match how people usually save and invest. A person might invest less in their twenties, more in peak earning years, pause during family or business changes, then make catch-up contributions before retirement.

Money Seasons lets you create multiple contribution periods by age. You can model one monthly investment from age 30 to 40, a different monthly contribution from age 40 to 50, and a yearly contribution from age 50 to retirement. That makes the lifetime investment projection easier to connect to actual life plans.

Planning for young investors

When you are just starting to invest, the biggest question is often not whether you have a perfect plan. It is whether small, repeatable contributions can become meaningful over time. Money Seasons helps younger investors test beginner investing scenarios like $50, $100, $250, or $500 per month, then compare what happens when those contributions rise with future income.

You can use it as a monthly investment calculator, Roth IRA growth calculator, 401(k) contribution planner, or long-term compound interest calculator. Add a lower contribution season for early career years, a higher saving rate after raises, and a different stock and bond allocation later in life to see how a realistic retirement savings path may develop.

Stock-only, stock-and-bond, and historical return modes

The calculator supports stock-only assumptions, stock and bond allocation assumptions, and historical stock and bond returns. In stock-and-bond mode, you can enter assumed stock returns and bond returns, then choose an allocation before and after retirement. In historical mode, Money Seasons uses annual S&P 500 total returns and 10-year Treasury bond returns from Aswath Damodaran's NYU Stern historical return data.

This makes it possible to compare a simple stock-only retirement plan, a stock and bond portfolio, a static bond amount, or a historical return path. It is not a prediction of the future, but it gives a clearer way to test assumptions than a single average return number.

Post-retirement withdrawals

A retirement calculator should not stop at retirement age. Money Seasons can continue the portfolio through retirement and model monthly withdrawals. You can test a withdrawal rate based on the initial retirement balance or a percentage of the current portfolio balance each year.

This helps answer questions like how a 4% withdrawal rate behaves, how stock and bond allocation affects retirement income, and how long a portfolio may last under different investment return assumptions.

Inflation-adjusted spending power

Future balances can look large in nominal dollars. The optional inflation view translates the projected ending balance into today's dollars, so you can estimate the spending power of a future portfolio. This is useful for retirement planning because a million dollars decades from now may not feel like a million dollars today.

What Money Seasons is best for

Money Seasons is best for long-term investing scenarios, financial independence planning, retirement planning, stock and bond allocation comparisons, and understanding how different saving periods affect compound growth. It is an educational calculator, not financial advice.

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