Why This Site Exists

Personal finance math is not complicated — but most tools that do it are locked behind paywalls, cluttered with ads, or require you to hand over an email address just to run a calculation.

This site exists to change that. Every calculator here runs entirely in your browser. No data is sent to a server. No account is required. No spreadsheet skills needed. You put in your numbers, you get your answer, and you keep your privacy.

The goal is simple: help people understand the math behind saving, investing, and reaching financial independence — so they can make better decisions for their own lives.

What You'll Find Here

This site offers a growing set of free tools and educational resources covering compound interest, retirement planning, and the FIRE (Financial Independence, Retire Early) movement.

Compound Interest Calculator

The core tool on this site. Enter an initial deposit, monthly contribution, interest rate, and time horizon. See an interactive chart showing exactly how your principal and interest grow year by year, along with your final balance.

FIRE Dashboard

A comprehensive retirement planning tool. Track your progress toward your FIRE number, model optimistic and pessimistic return scenarios, explore the impact of mortgage paydown, and see how small changes in savings rate dramatically shorten your timeline.

Coast FIRE Calculator

Coast FIRE is the idea of saving enough early that compound growth alone carries you to retirement — without another dollar of contributions. This calculator finds your Coast FIRE number and shows how far along you already are.

FI Insights

Data-driven context for your financial journey. Savings benchmarks by age, millionaire statistics, the first $100K phenomenon, and an interactive Rule of 72 explorer — all in one place.

Our Philosophy

Privacy First

Every calculation runs locally in your browser using WebAssembly. We never see your numbers. We don't store them, transmit them, or log them. Your financial situation is yours alone. We use Google Analytics to understand which tools are most useful (page views, not personal data), and Google AdSense to keep the site free. See our Privacy Policy for full details.

Education Over Sales

Nothing on this site is financial advice, and nothing here is trying to sell you a product. We don't recommend brokers, push affiliate links for financial products, or suggest you buy anything. The calculators are educational tools. Use them to build intuition, run scenarios, and ask better questions of a qualified financial advisor if you need one.

Free, Always

Every tool on this site is and will remain free. The site is supported by non-intrusive display advertising. If you'd like to support the project directly, there's a link in the footer. No pressure either way.

Who Is This For?

These tools are useful for anyone at any stage of their financial journey:

Beginners who want to understand why "start saving early" actually matters — the compound interest calculator makes it visual and tangible.

Mid-career savers who want to know if they're on track and how much longer they need to keep working at their current pace.

FIRE enthusiasts modeling aggressive savings scenarios, exploring Coast FIRE, or stress-testing their withdrawal strategy against different return assumptions.

Parents and educators looking for a clear, jargon-free way to demonstrate the power of compounding to younger people.

Editorial Standards & Methodology

WealthCompounds is an independent personal-finance education project. Every article and calculator on this site is researched, written, and reviewed in-house by our editorial team before it is published, and is revisited periodically to keep figures and references current.

How our calculators work

Our tools use standard, well-established financial formulas — compound interest, the future value of a series of contributions, the 4% safe-withdrawal rule, and the Rule of 72. We document the assumptions behind each tool (constant returns, no taxes or fees unless stated, real versus nominal rates) directly on the page, so you can see exactly what the math does and does not account for.

How we source our content

Statistics and benchmarks — savings rates, median retirement balances, historical market returns — are drawn from primary, publicly available sources such as the Federal Reserve Survey of Consumer Finances, the Bureau of Labor Statistics, and long-run market-return data. We favor primary data over secondary commentary, and we state the time period and assumptions behind any figure we cite.

Accuracy and corrections

We review our calculators and articles for accuracy and update them as data and best practices change. If you spot an error or believe a figure is out of date, we want to know — we review reported issues and amend our content promptly.

Editorial independence

We do not sell financial products, accept payment to feature specific brokers, or publish sponsored "advice." The site is funded solely by non-intrusive display advertising, which is kept entirely separate from our editorial content. Nothing here is personalized financial advice — for decisions specific to your situation, consult a qualified professional.

A Note on Accuracy

The calculators on this site use standard financial formulas for compound interest and retirement projections. They are designed to give you accurate ballpark figures for planning purposes.

That said, real-world investing involves taxes, fees, variable returns, inflation, and life events that no calculator can fully model. The numbers you see here assume constant rates and no withdrawals during the accumulation phase. Treat the results as directional guidance — a starting point for planning, not a guarantee.

For major financial decisions, always consult a qualified financial professional. See our Terms of Service for full disclaimers.

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