How Social Security Benefits Are Calculated Based on Lifetime Earnings
Your Social Security benefit comes from a formula: SSA averages your highest 35 years of indexed earnings, then replaces 90%, 32%, and 15% of different slices of that average. See each step explained, the 2026 and 2027 bend points, and a calculator that shows the math.
Written and fact-checked by the CheckPayDate.com Editorial TeamPublished October 28, 2026Last reviewed October 28, 2026How we review
Quick Answer
SSA takes your highest 35 years of earnings, adjusts them for wage growth, and averages them into a monthly figure called AIME. It then applies a three-part formula to get your PIA — your monthly benefit at full retirement age. For someone turning 62 in 2027, the PIA is:
+ 32% × AIME from $1,340 to $8,077
+ 15% × AIME above $8,077
How Social Security Works in 5 Steps
- Step 1
Earn credits
You need 40 credits — about 10 years of work — to qualify for retirement benefits. You earn up to 4 credits a year; one credit takes $1,890 of earnings in 2026 and $1,970 in 2027.
- Step 2
Index your earnings
SSA adjusts each year's earnings for growth in average wages up to the year you turn 60, so older earnings count in today's terms. Earnings at 60 and later count at face value. Only earnings up to each year's taxable maximum count.
- Step 3
Average your highest 35 years (AIME)
SSA adds your 35 highest indexed years and divides by 420 months. If you worked fewer than 35 years, zeros fill the gap and pull your average down. The result is your Average Indexed Monthly Earnings, rounded down to the dollar.
- Step 4
Apply the benefit formula (PIA)
Your Primary Insurance Amount is 90% of AIME up to the first bend point, plus 32% up to the second, plus 15% above that, rounded down to the dime. This is your benefit at full retirement age.
- Step 5
Adjust for when you claim
Claiming at 62 cuts the PIA by up to 30%; waiting past full retirement age adds 8% a year until 70. COLAs are added each year starting at age 62, even if you haven't claimed.
Work Credit Checker
How many credits you'll earn this year, and how close you are to 40
You need 16 more credits — about 4 more years at this pay.
Disability and survivor benefits can need fewer credits, depending on age. Check SSDI eligibility.
Benefit Formula Calculator
See exactly how your average earnings become a monthly benefit
The math, step by step
- 1. Top 35 years: $60,000 × 35 years = $2,100,000
- 2. AIME: $2,100,000 ÷ 420 months = $5,000 a month
- 3. 90% slice: 90% × $1,340 = $1,206.00
- 4. 32% slice: 32% × $3,660 = $1,171.20
- 5. 15% slice: 15% × $0 = $0.00
- 6. PIA (benefit at full retirement age): $2,377.20 a monthAbout 47.5% of your average earnings. Rounded down to the dime, as SSA does.
Social Security Bend Points by Year
| Year you turn 62 | First bend point | Second bend point | Max PIA from formula* |
|---|---|---|---|
| 2026 (born 1964) | $1,286 | $7,749 | $4,369.40 |
| 2027 (born 1965) | $1,340 | $8,077 | $4,554.00 |
*If every one of 35 years were at that year's taxable maximum, a simplification. SSA's published maximum benefit is lower because past years had lower maximums.
Why the Formula Favors Lower Earners
The first slice of your average earnings is replaced at 90%, but the top slice at only 15%. A worker averaging $30,000 a year gets back a much larger share of their pay than one averaging $150,000 — even though the higher earner gets a larger check in dollars. Try both in the calculator to see the difference.
What This Calculator Simplifies
- It treats your average as already indexed. SSA indexes each year separately using the national average wage index.
- It caps every year at the current taxable maximum. Past years had lower caps.
- It doesn't include COLAs after 62, claiming-age adjustments, or spouse and survivor benefits.
For your real numbers, check your earnings record and estimates in my Social Security.
Frequently asked questions
Related guides & tools
Official Primary Data Sources
Formula and bend points from SSA's Office of the Chief Actuary, checked October 28, 2026. The calculator simplifies indexing; your official estimate is in your Social Security Statement.
PIA bend points: $1,286 / $7,749 (2026) and $1,340 / $8,077 (2027).
The 90% / 32% / 15% formula and rounding rules.
How AIME is computed from the highest 35 years of indexed earnings.
The wage index used to index past earnings.
40 credits for retirement; up to 4 per year.
2027 quarter of coverage ($1,970) and taxable maximum ($192,300).