Retire at 45 — what monthly savings does it take?
FIRE number: $1,250,000 ($50,000/year × 25.0). At 7% real return saving $4,000/month from $50,000, you reach it in 15 years — age 45. Savings rate: 49%.
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Frequently asked questions
What's the FIRE number for retire at 45 — what monthly savings does it take??
FIRE number = annual expenses × (100 / SWR). For $50,000/year expenses at 4% SWR: $50,000 × 25.0 = $1,250,000.
How many years to reach this FIRE number?
Starting with $50,000 and saving $4,000/month at 7% real return, you reach $1,250,000 in 15 years at age 45. Total contributed in the simulation: $770,000; growth: $574,145.
What savings rate does this require?
$48,000/year saved out of an implied $98,000 income = 49% savings rate. This is an arithmetic scenario; the result changes with income, expenses, contributions, taxes, fees and return assumptions.
What if my real return is different?
Keeping this scenario's balance, expenses, contributions and 4% SWR fixed, a 5% real-return sensitivity reaches the target in 17 years; an 8% sensitivity reaches it in 14 years. These are constant-return illustrations, not forecasts.
How this number was calculated
FIRE number = Annual expenses × (100 / SWR)
= $50,000 × 25.0
= $1,250,000
Years to FIRE: solve bal × (1 + r) + annual_contrib = FIRE
starting bal = $50,000
annual_contrib = $48,000
r (real return) = 0.07
→ 15 years (age 45)
Total contributed = $770,000
From growth = $574,145 (46% of FIRE number)Math grounded in the Trinity Study (Cooley et al., 1998) and Karsten Jeske's SWR Series.
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Open the FIRE calculator →Educational projection. Future returns are not guaranteed. Sequence-of-returns risk matters for early retirees — see Karsten Jeske's SWR Series for nuanced analysis. Verified 2026-05-27.