Coast FIRE Calculator with Social Security (Free, 2026)

Your future benefit is retirement income. See how much less you need invested today — whether you count all of it, most of it, or none.

$329,443

$182,913

With Social Security

Save $146,530 (44%)
27%$50,000
35years
Building
2gap yrs
Include Social Security

How much of it do you count?

From your SSA statement, in today's dollars. The 2026 average is about $2,071/mo. Many planners count 75% to stay conservative.

Your Information

How Social Security Changes Your Target

Social Security offset44% less
Before
$329,443
After
$182,913
Benefit counted (100%)
$24,000/yr

2-year gap

You retire at 65 but claim at 67 • Need $100,000 bridge fund

What this calculator works out

What it calculates

Coast FIRE is the point where you can stop saving for retirement — what you've invested will grow to your full retirement target on its own. This calculator shows that number two ways: with and without your Social Security benefit. Counting the benefit shrinks the target, often by a third or more. It does not estimate the benefit itself — get that from your statement at ssa.gov first.

The formula, in plain English

Four steps do all the work:

  1. 1.Full FIRE number = annual spending ÷ 4%. This is the pot you'd need to retire on today using the 4% safe withdrawal rule.
  2. 2.Social Security offset = the yearly benefit you count ÷ 4%. Counting $24,000 a year works like having an extra $600,000 invested. If you claim later than you retire, the offset shrinks a little for the waiting years.
  3. 3.Adjusted target = Full FIRE number − Social Security offset.
  4. 4.Coast FIRE number = adjusted target ÷ (1 + real return) raised to the years until retirement.

Real return means growth after inflation — 7% growth with 3% inflation is about 3.9% real. Every figure is in today's dollars.

A worked example

Take someone who is 30, spends $50,000 a year, retires at 65, and expects $2,000 a month starting at 67. Without Social Security they need about $329,000 invested today. Count the full benefit and that falls to about $183,000 — 44% less. Even counting just 75% of it, the target is still only about $220,000.

Should you count Social Security at all?

This is the most argued question in every FIRE forum. There are three honest answers, and the right one depends on how much risk you can live with.

Count all of it

Social Security is paid from payroll taxes that keep flowing in, and cutting a benefit that millions of voters live on would be political suicide. People in this camp enter their full statement estimate.

Count 75–80% — the planning favorite

SSA's trustees project the trust fund runs short in the early 2030s. Even then, ongoing taxes would still cover about 77% of benefits if Congress did nothing. Counting 75–80% bakes in that documented worst case.

Count none of it

The most conservative camp plans as if the benefit were $0 and treats whatever arrives as a bonus — extra margin for health costs and surprises. Your target is highest, but nothing can derail it.

What each choice does to your Coast FIRE number

Same person as the example above — age 30, $50,000 spending, retiring at 65, $2,000/month claimed at 67:

You countYearly benefit usedCoast FIRE number
100%$24,000~$183,000
75%$18,000~$220,000
50%$12,000~$256,000
0%$0~$329,000

Pick your own trust level in the calculator above — the result updates instantly with your numbers.

How much Social Security will you get?

Don't guess. The most accurate number is your Social Security statement at ssa.gov, which uses your real earnings record. For scale, here are the official 2026 figures:

2026 figureAmount
Average retired-worker benefit$2,071/mo
Maximum if you claim at 62$2,969/mo
Maximum at full retirement age (67)$4,152/mo
Maximum if you wait until 70$5,181/mo
Cost-of-living adjustment (COLA)+2.8%

Maximums assume you earned the taxable cap every year from age 22 — most people get far less. SSA's Quick Calculator gives a rough estimate without your records, but your statement is the number to use here.

Claiming at 62 vs 67 vs 70 — does it matter?

Your claiming age moves the benefit a lot. If you were born in 1960 or later, your full retirement age is 67. Claim at 62 and your check shrinks by about 30% for life. Wait past 67 and it keeps growing — the official 2026 maximums run $2,969 at 62, $4,152 at 67, and $5,181 at 70.

For Coast FIRE, two forces pull against each other. Claiming later means a bigger benefit and a bigger offset. But it also means more years between retiring and claiming — years your portfolio covers alone. The calculator flags those gap years and the bridge money they need, so try 62, 67 and 70 and watch your number move.

Rule of thumb from the forums: claiming early wins if you don't expect a long retirement; waiting wins if longevity runs in your family. As one heavily upvoted Reddit answer put it — the main consideration is your life expectancy.

Have a government pension? WEP is gone

Updated for the 2025 law

For decades, the Windfall Elimination Provision (WEP) and Government Pension Offset (GPO) cut Social Security for teachers, firefighters, police officers and other public workers whose pension came from a job that didn't pay Social Security taxes. Older guides still tell you to slash your estimate because of them.

That advice is out of date. The Social Security Fairness Act, signed on January 5, 2025, ended WEP and GPO — retroactive to benefits payable for January 2024. If the old rules applied to you, your statement now shows the full amount, and you can enter it here as-is. About 72% of state and local employees were never affected, because their work was already covered.

Sources and methodology

Benefit figures come straight from the Social Security Administration and are checked against the official 2026 amounts.

Figures use official 2026 SSA amounts · last reviewed June 2026.

Educational only — not financial advice. Benefits depend on your earnings record and future law; markets don't grow in a straight line. Everything runs in your browser — nothing you enter is stored.

How to use this calculator

1

Get your benefit estimate

Log in at ssa.gov and open your Social Security statement — it projects your monthly benefit from your real earnings. No statement handy? Start with the 2026 average of about $2,071 a month and refine later.

2

Enter your basics

Fill in your age, what you've already invested, your planned yearly spending in retirement, and the age you want to retire.

3

Set your claiming age and trust level

Choose when you'll start the benefit (62–70) and how much of the estimate to count — 100%, 75%, 50% or none. Many planners use 75% to stay conservative.

4

Read both numbers

You get your Coast FIRE number with and without Social Security, plus the savings between them. If you retire before your claiming age, the calculator flags the gap years your portfolio must bridge.

Frequently Asked Questions

There's no single right answer — it's a risk choice. Counting the full benefit gives the smallest target; counting none gives the biggest safety margin. The most popular middle ground in FIRE communities is 75–80%, which matches the documented worst case of about 77% of benefits staying payable. This calculator lets you pick any of those with one tap.

New to the idea? Read our guide on what Coast FIRE is.

"It's not that I don't want to work hard—I just want to work hard for myself."

May you reach the shore soon 🌅