Step 1: Know Your Retirement Number
Before calculating how to get there, you need to know where "there" is. The most widely used rule is the 4% Rule (also called the "safe withdrawal rate"): in retirement, you can withdraw 4% of your portfolio each year with a high probability of your money lasting 30+ years.
| Annual Retirement Spending | Retirement Number (4% Rule) |
|---|---|
| $40,000/year ($3,333/mo) | $1,000,000 |
| $60,000/year ($5,000/mo) | $1,500,000 |
| $80,000/year ($6,667/mo) | $2,000,000 |
| $100,000/year ($8,333/mo) | $2,500,000 |
Step 2: Project Your Growth with Compound Interest
Adjust the inputs to match your current savings, expected return, and monthly contribution. The calculator shows year by year whether you're on track for your retirement number.
Benchmark: Retirement Savings by Age
Fidelity recommends these savings milestones (as a multiple of your annual salary):
| Age | Target Savings | Example ($75k salary) |
|---|---|---|
| 30 | 1× salary | $75,000 |
| 35 | 2× salary | $150,000 |
| 40 | 3× salary | $225,000 |
| 45 | 4× salary | $300,000 |
| 50 | 6× salary | $450,000 |
| 55 | 7× salary | $525,000 |
| 60 | 8× salary | $600,000 |
| 67 (retirement) | 10× salary | $750,000 |
The Impact of Starting Early vs. Late
Recommended Retirement Savings Order
Emergency fund first — 3–6 months of expenses in a high-yield savings account before investing
401(k) to the employer match — free money, instant 50–100% return on those dollars
Max Roth IRA — $7,000/year of tax-free compounding is too good to pass up
Back to 401(k) — continue up to the $23,500 annual limit
Taxable brokerage — once tax-advantaged accounts are maxed