Compound Interest Calculator (aka FIRE Calculator) is a free compound interest calculator and retirement planning tool for people chasing Financial Independence, Retire Early (FIRE). Whether you are aiming for Lean FIRE, Coast FIRE, Barista FIRE, or Fat FIRE, use it to project your nest egg, model savings rate and contributions, and see how compounding can grow your portfolio over time.
Compound interest is interest earned on interest. When investment returns are reinvested, each period earns on your principal plus previously accumulated gains. That compounding snowball is the engine behind long-term investing, passive income goals, and building enough invested assets to cover living expenses in early retirement.
Plan short-term savings and multi-decade FIRE timelines in one place. Set starting principal, expected annual return, contribution or withdrawal amount, contribution frequency, compounding frequency, and time horizon. Switch between contribution mode for accumulation and withdrawal mode for drawdown planning, including scenarios inspired by safe withdrawal rate thinking and the 4% rule. Review projected balances, charts, and year-by-year tables so you can stress-test your FI number before you leave full-time work.
Features included:
- Calculate future value with the compound interest formula
- Contribution and withdrawal modes for growth and retirement drawdown
- Contribution frequencies including monthly, quarterly, semiannually, and daily
- Smart Insight tips based on your calculation
- Graph and table views under your results
- Formulas included for reference
- Save, reorder, and share calculations with friends or your FIRE community
- Dark Mode and Light Mode