Coast FIRE Calculator with Social Security (2026)
Social Security can cut your Coast FIRE target a lot — or leave a hole if the check is smaller than you planned. Compare four personal scenarios from one SSA estimate.
$329,443without Social Security
$182,913
Coast FIRE target · 100% Social Security
27% · $50,000 saved
$574/mo to reach Coast
From 65 to 67, $100,000 of spending is already in this target.
Example scenario. Replace these values with your own.
Paste the SSA monthly amount for this age. This page does not estimate it. Get it from SSA
Count this much of the benefit
Your Information
Assumptions
7% return, 3% inflation, 4% withdrawal · today's dollars
What does this Coast FIRE target mean?
It's how much you need invested today after treating part of your Social Security estimate as retirement income.
Coast FIRE itself does not include Social Security. The four boxes let you count 100%, 78%, 50%, or none of the amount you paste in.
The example on this page is age 30, retire at 65, $50,000 a year, $50,000 already saved, and $2,000 a month starting at 67. Counting 100% of that check drops the Coast target from $329,443 to $182,913 (today's dollars, 7% nominal return, 3% inflation, 4% withdrawal).
From 65 to 67 the plan still needs $100,000 of spending from savings or other income. That gap is already inside the $182,913. It is not extra on top.
Tap 78% ($215,149) or 50% ($256,178) to see those targets. Get the monthly figure from SSA. This page does not estimate it.
Which SSA estimate belongs here?
The claiming age and monthly amount have to be a matching pair.
This page does not estimate the benefit or convert one age's amount into another.
- •Use the monthly figure shown for the claiming age you selected
- •If you change the age, confirm the matching amount before trusting the result
- •If you will earn less or stop early, fix the SSA future-earnings assumption first
Adjust expected future income in your SSA retirement estimate
What do the four targets show you?
Four ways to count the same benefit, not four forecasts of your check.
Each row applies a different percentage to the amount you entered:
- •100%: the full amount you entered
- •78%: the dated 2026 OASI reserve-depletion figure
- •50%: a tool stress test, not an SSA projection
- •0%: Social Security turned off
A lower target means more future spending is assigned to Social Security. You have not already saved that difference.
How do you get $182,913 from the example?
Same defaults as the calculator. All amounts are in today's dollars.
- 1.Retirement target without Social Security: $50,000 ÷ 4% = $1,250,000 at age 65.
- 2.Discount that 35 years at about 3.88% real return (7% nominal, 3% inflation): $329,443 today. That is the 0% Coast target.
- 3.Count $2,000 × 12 = $24,000 a year from age 67. At 4%, that income is worth $600,000 if it started at 65. It starts two years later, so the offset at 65 is $555,979.
- 4.$1,250,000 − $555,979 = $694,021 still needed at 65. Discount that to today: $182,913.
- 5.Ages 65–67 still cost $50,000 a year with no Social Security yet: 2 years, $100,000, already inside the target.
- 6.The same $2,000 benefit at 78% / 50% / 0% gives Coast targets of $215,149 / $256,178 / $329,443.
Swap in your own SSA pair. The page does not estimate or correct the benefit.
What does the result leave out?
Use the number to compare planning assumptions, not as a benefit estimate or retirement recommendation.
- •Federal or state tax
- •Medicare premiums
- •Spousal or survivor benefits
- •Claiming-age advice
- •Future changes to Social Security law
- •Estimating or correcting your benefit amount
If you need to combine Social Security with a pension, use the Pension Coast FIRE calculator.
Where do these sources and the 78% figure come from?
The 78% figure and the benefit-input workflow come from SSA sources. The Coast FIRE math runs from the values you enter.
What does the 78% scenario mean?
It is a dated OASI pressure test, not a prediction of your personal check.
The 2026 Trustees Report projects that Old-Age and Survivors Insurance (OASI) reserves will be depleted in 2032. Continuing income would then cover 78% of scheduled OASI benefits. This page uses that 78% figure only as a dated scenario.
Why check future earnings before you paste an estimate?
Many statements assume you keep earning at a similar pace.
Your SSA retirement estimate lets you adjust expected future income. If you plan to reduce pay or stop work, enter income that matches that plan before copying the monthly amount here.
- 2026 OASDI Trustees Report, OASI reserve projection and payable percentage (ssa.gov)
- Social Security Statement, personalized estimates based on your earnings record (ssa.gov)
- Retirement benefit estimate with an expected future income adjustment (ssa.gov)
- Social Security Fairness Act, WEP and GPO repeal (ssa.gov)
Sources last reviewed: July 25, 2026.
Results are educational planning estimates. Benefits depend on the amount you enter and on future law. Market returns also vary. The calculator runs in your browser and does not store your inputs.
How do you use this Coast FIRE calculator with Social Security?
Where do you get the benefit amount?
Pick one claiming age and copy the monthly estimate for that same age from your Social Security statement or an SSA calculator.
What Coast FIRE inputs do you enter?
Add current age, savings, monthly contribution, annual retirement spending, and retirement age.
How do you confirm the age and amount?
Enter the claiming age and its matching monthly benefit, then confirm the pair. Changing either value pauses the result until you confirm again.
Which percentage drives the main result?
Pick 100%, 78%, 50%, or 0%. The highlighted box is the Coast target at the top.
Frequently asked questions
No. A Coast FIRE number is the invested amount only. This page lets you count 100%, 78%, 50%, or none of an SSA estimate you paste in. It does not estimate the benefit.
They apply four percentages to the same benefit you entered. 100% counts all of it. 78% is the dated 2026 OASI pressure figure. 50% is a tool stress test. 0% turns Social Security off. Dollar amounts for the default example are in the worked calculation above.
The 2026 Trustees Report projects OASI reserve depletion in 2032, when continuing income would cover 78% of scheduled OASI benefits. This page uses that report figure as a dated scenario, not as a prediction of your individual payment. Official 2026 figures for scale: $2,071/mo average retired-worker benefit; maximums of $2,969 at 62, $4,152 at full retirement age (67), and $5,181 at 70; +2.8% COLA. Maximums assume you earned the taxable cap every year from age 22. Most people get far less, so use your own statement at ssa.gov.
The monthly figure for the claiming age you selected. If the SSA estimate assumes continued future earnings and you plan to earn less or stop early, change that assumption on ssa.gov first.
Each claiming age has its own estimate, and this tool will not convert one into another. If you were born in 1960 or later, full retirement age is 67: claiming at 62 cuts the check by about 30% for life. Official 2026 maximums are $2,969 at 62, $4,152 at 67, and $5,181 at 70.
The Social Security Fairness Act, signed January 5, 2025, ended WEP and GPO, retroactive to benefits payable for January 2024. Older guides that tell public-sector workers to slash their estimate are out of date. If those rules used to apply to you, your statement now shows the full amount and you can enter it here. About 72% of state and local employees were never affected because their work was already covered. To combine Social Security with pension income, use the Pension calculator.
No. It uses one entered benefit. For a household Coast FIRE number, use the Couples calculator and bring a verified benefit for each person.
Read the Coast FIRE guide for the basic concept and formula.
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