FIRE Calculator
Financial Independence, Retire Early — find your magic number
FIRE — Financial Independence, Retire Early — isn't just for extreme savers. It's a framework for understanding how much you need before employment income becomes optional. Even if full FIRE isn't your goal, knowing your number makes every financial decision clearer and more deliberate.
Your Numbers
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FIRE Number (Target Portfolio)
£0
Amount needed to retire on withdrawals alone
Years to FIRE
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£0Still to Accumulate
£0Monthly Income at FIRE
∞Years of Runway (4% rule)
£0Coast FIRE Number (today)
FIRE Progress0%
🔥Based on the 4% rule — historically, this allows indefinite portfolio withdrawals without running out of money.
🇬🇧 UK FIRE — what this calculator doesn't model
🪣 The Two-Pot Problem
UK FIRE savings split across a SIPP (pension — inaccessible before age 57) and ISAs (accessible any time). If you plan to FIRE at 45, only your ISA and other liquid assets are accessible until you reach 57 — your SIPP is locked regardless of how large it is. Your effective early-retirement FIRE number is your ISA balance, not your total pot.
🏛️ State Pension Bridging
If you FIRE at 45 and the State Pension kicks in at 67, you have a 22-year gap to fund entirely yourself. After 67, the State Pension (~£11,500/year) reduces how much you need to draw. This calculator treats expenses as flat forever — a more accurate model reduces your required withdrawal after your State Pension age.
💸 Tax on Drawdown
ISA withdrawals are tax-free. SIPP withdrawals (after 25% tax-free lump sum) are taxed as income. Withdrawing £30,000/year from a SIPP means paying income tax on the portion above your personal allowance (£12,570). The tax-efficient UK FIRE strategy draws from the ISA first, refills it annually from the SIPP within the personal allowance, deferring tax as long as possible.