Finance Guides & Articles
Free, jargon-free guides on compound interest, retirement planning, and investment growth — written to help you make better financial decisions with clear numbers.
Rule of 72 Explained — How Long to Double Your Money?
The Rule of 72 tells you how long to double your money at any interest rate. At 7%, money doubles in 10.3 years. Free calculator included.
Compound Interest vs Simple Interest — The Real Difference
Simple interest earns only on principal. Compound interest earns on principal plus past interest. On $10,000 at 7% for 20 years: $14,000 vs $38,697.
Roth IRA vs 401(k): Which Is Better for You in 2026?
Roth IRA uses after-tax dollars, grows tax-free. 401(k) reduces taxable income now, taxed at withdrawal. The right choice depends on your current vs future tax rate.
How Much Will $10,000 Grow in 20 Years? (Calculator + Table)
$10,000 at 7% for 20 years grows to $38,697 — that is $28,697 in pure compound interest. See the year-by-year breakdown and compare 5%, 7%, and 10% scenarios.
What Is a Good 401(k) Return Rate? (2026 Benchmarks)
A good 401(k) return is 5–8% annually after fees. The S&P 500 averages 10.5% nominal, 7% inflation-adjusted since 1957. See how your rate compares.
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