FIRE Planner

Model current cash, investment assets, monthly income allocation, and post-FIRE target structure in one place.

Savings Rate: 40%
Post-FIRE Monthly Gap: ¥10,000/mo
Post-FIRE Cash Ratio: 10%
Inputs
Start with current asset mix and income allocation, then define the post-FIRE target structure.

1. Current Position

Enter current cash, investments, and monthly income allocation.

Deposits, money market funds, emergency reserves, and lower-volatility assets.

Stocks, funds, ETFs, crypto assets, and other long-term investments.

Stable, durable disposable income.

Current lifestyle cost, excluding intentional new investments.

The amount you intentionally route into investments each month.

Current Cash / Investment Mix

16.7% / 83.3%

Monthly Net Savings

¥8,000

Cash Left After Investing

¥2,000

The portion still left in cash after monthly expenses and investment contribution.

Savings Rate

40%

2. Growth Assumptions

These control investment growth and withdrawal safety.

Used for pre-FIRE investment growth assumptions.

Used to size the post-FIRE investment corpus. 3.5% - 4.5% is common.

Common Return Rates
Common Withdrawal Rates

3. Post-FIRE Assumptions

These define the investment and cash structure of the FIRE target.

Estimate the lifestyle cost you expect after FIRE.

Rent, pension, side work, or other stable cash flow. Use 0 if none.

Target cash share after FIRE. 10% is the default balanced assumption.

Common Post-FIRE Cash Ratios

Post-FIRE Monthly Gap

¥10,000/mo

Post-FIRE Investment Ratio

90%

Results auto-refresh after changes. Use the button to refresh immediately.

Projection
The result shows target assets, cash/investment split, progress, and growth path.

Run the first projection

After you fill in the inputs, this panel will show time to goal, target composition, and the growth path.

Core Formulas
Why this model

Total FIRE Target = Required Investment Corpus / Post-FIRE Investment Ratio

The post-FIRE cash ratio defines how target assets split between cash and investments.

Monthly Investment Growth = Investments x (1 + Monthly Return) + Monthly Investment Contribution

Cash assets grow or shrink by monthly cash retained.

Annual Retirement Gap = max(Post-FIRE Monthly Expense - Other Monthly Income, 0) x 12

First measure how much post-FIRE spending must be supported by the investment portfolio.

Monthly Return = (1 + Annual Return)^(1/12) - 1

This uses an effective monthly return instead of Annual / 12.

This tool is designed for strategy and decision support, not professional financial advice.