Financial Planning Software for DIY Investors
Planning software turns 'am I saving enough?' into a number. Here's what these projection tools model, what they can't, and which free and paid options to know.
Don't have time? Here's what you need to know:
- 1Planning software projects your savings forward and, in the best tools, reports a Monte Carlo success probability.
- 2Empower offers free planning tools; Boldin is a well-regarded paid tool for detailed DIY retirement modeling.
- 3Output quality depends entirely on assumptions — use realistic, conservative return inputs to avoid under-saving.
- 4Treat results as directional, not guaranteed; the real value is seeing how saving more or working longer helps.
What Planning Software Actually Does
A portfolio tracker tells you where you are today. Financial planning software tries to answer a harder question: where are you headed? It takes your current savings, contributions, expected returns, retirement age, and spending, and projects them forward — usually to estimate whether your money is likely to last through retirement.
The better tools don't just multiply by a fixed growth rate. They run a Monte Carlo simulation, testing your plan against hundreds or thousands of randomized market scenarios, then report a probability of success — for example, 'your plan succeeds in 85% of simulated markets.' That probability framing is more honest than a single straight-line projection, because real returns are volatile and the order of good and bad years matters.
Inputs and Outputs That Matter
Most planning tools accept the same core inputs and produce a handful of outputs. Understanding what each does helps you judge whether a tool is doing real work or just compounding a single number.
| You enter | It estimates |
|---|---|
| Current savings & accounts | Projected balance at retirement |
| Monthly/annual contributions | Probability the plan lasts (Monte Carlo) |
| Target retirement age | Sustainable annual spending |
| Expected spending in retirement | Effect of claiming Social Security early vs late |
| Asset allocation / expected return | Sensitivity to lower returns or higher inflation |
| Other income (pension, Social Security) | Tax-aware withdrawal sequencing (some tools) |
Tip: Run the plan twice — once with optimistic returns and once with conservative ones. The gap between them is your real margin of safety.
Free and Paid Options to Know
Empower (formerly Personal Capital) offers a free set of planning and net-worth tools, including a retirement planner with Monte Carlo simulation; it's funded by an advisory business, so expect outreach about its paid services. For deeper do-it-yourself planning, Boldin (formerly NewRetirement) is a well-regarded subscription tool built specifically for detailed retirement modeling, including withdrawal strategies, Roth conversions, and Social Security timing.
Beyond those, many brokerages bundle a retirement planner with your account at no extra cost, and the Bogleheads community wiki and forum are an excellent free resource for understanding the assumptions behind any projection. Pricing and feature sets change, so verify current details before relying on any specific tool.
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Where the Projections Break Down
Every projection is only as good as its assumptions, and the assumptions are guesses about the future. Garbage in, garbage out applies forcefully here: a plan that assumes a 9% return every year will look great and may set you up to under-save. Use forward-looking return assumptions that are realistic and modestly conservative, and remember that the U.S. stock market's long-run average of roughly 10% nominal includes deep, multi-year drawdowns along the way.
Treat the output as a directional guide, not a promise. A plan with an 85% success probability is not a guarantee, and a single percentage can lull you into false precision. The real value of these tools is comparative — seeing how much one more year of work, a lower spending target, or a higher savings rate moves the needle. For the underlying growth math, our ETF return calculator and compound interest guide show how contributions and time interact.
Important: Planning software is educational, not personalized advice. For high-stakes decisions — early retirement, large Roth conversions, complex pensions — consider validating the plan with a fee-only fiduciary advisor.
Frequently Asked Questions
What is a Monte Carlo simulation in retirement planning?
It tests your plan against hundreds or thousands of randomized market scenarios instead of a single fixed return, then reports a probability of success — for example, your savings lasting in 85% of simulated markets. It's more honest than a straight-line projection because it captures how market volatility and the order of returns affect outcomes.
Is there free financial planning software?
Yes. Empower offers free planning and net-worth tools with a Monte Carlo retirement planner (it markets paid advisory services alongside them), many brokerages bundle a planner with your account, and the Bogleheads wiki and forum are an excellent free resource for the assumptions behind any plan.
How accurate are these retirement projections?
Only as accurate as their assumptions, which are guesses about future returns, inflation, and spending. Use realistic, modestly conservative return inputs, and treat the output as directional. The biggest value is comparative — seeing how working one more year or saving more changes the result — not the precise final number.
What return assumption should I use?
Lean conservative. The U.S. stock market's long-run average is roughly 10% nominal before inflation, but it includes deep multi-year drawdowns, and a bond-heavy or near-retirement portfolio earns less. Planning with a lower assumed return builds in a margin of safety rather than setting you up to under-save.
Further Reading
Free Tools
Alex Harrington
CFA Level II Candidate, Finance & Economics
Alex Harrington is an independent ETF researcher and personal finance writer with over 8 years of experience analyzing exchange-traded funds. A CFA Level II candidate with a background in economics, Alex has reviewed 800+ ETFs and helped thousands of beginners build their first investment portfolios through clear, jargon-free education.
This content is for educational purposes only and does not constitute financial advice. Past performance does not guarantee future results. Consult a licensed financial advisor before making investment decisions.