Wealth Acceleration — Expert Insights & Guides
Compound interest, retirement, and FIRE math — the tools and guides for growing wealth over decades.
The Rule of 72: How to Estimate When Your Money Doubles
Divide 72 by your annual rate of return to find how long it takes to double your money. Learn the formula, its 1494 origins, why 72 beats 70 and 69.3 for mental math, and how the same rule exposes the true cost of high-interest debt.
How to Start Investing: The Right First Steps in the Right Order
Start investing by capturing the employer 401k match, then funding a Roth IRA, then returning to the 401k. This guide explains the priority sequence, why index funds beat stock-picking for most people, and how $200/month at 25 becomes $526,000 by 65.
Average Net Worth by Age in 2026: What the Benchmarks Actually Mean
The median U.S. net worth at 35 is $47,000; at 55 it's $217,000. This guide shows the Fed's 2022 SCF data, Fidelity's savings-rate milestones, why the average is three times the median, and the two levers that actually move your number.
What Is Dollar Cost Averaging — And Does It Actually Work?
Dollar cost averaging invests a fixed amount at regular intervals, automatically buying more shares when prices are low. Learn how DCA works, how it compares to lump-sum investing, and why it is the default strategy for most long-term investors.
2026 Backdoor Roth IRA: Pro-Rata Rule Explained With Examples
The backdoor Roth IRA lets high earners above the 2026 income limits ($150K single / $236K married) fund a Roth IRA. The pro-rata rule determines how much of your conversion is taxable — with three worked examples and a reverse rollover solution.
What Is the 4% Rule? The Safe Withdrawal Rate Explained
The 4% rule says you can withdraw 4% of your retirement portfolio each year without running out of money over 30 years. Here is where it came from, how to calculate it, and when to use 3.5% instead.
Roth IRA vs 401k: Which Should You Prioritise in 2026?
Roth IRA vs 401k: the right answer for most people is both, in the right order — employer match first, then Roth IRA, then back to 401k. This guide explains the tax logic, 2026 limits, income phase-outs, and the exact priority sequence.
How Much Do I Need to Retire? Calculating Your Retirement Number
Your retirement number = annual expenses × 25. This guide explains the 4% rule, shows how to calculate your personal number step by step, adjusts for early retirement and Social Security, and includes Fidelity's age benchmarks.
How to Calculate Compound Interest: Step-by-Step with Examples
Learn how to calculate compound interest using the formula A = P(1 + r/n)^nt with worked examples, a comparison table, and a free compound interest calculator.