Mochiru: Asset Longevity Sim

Mochiru is a fully offline retirement asset longevity simulator covering your whole financial lifecycle: accumulation, retirement, and drawdown. It answers one question with Monte Carlo simulation: how long will your money last?

WHO IT IS FOR

• You want to see, in numbers, how many years your retirement assets will last
• You are planning FIRE / early retirement and want distributions, not a single optimistic line
• You want a drawdown plan that includes your pension, on your own assumptions
• You want everything on-device: no account linking, no sign-up

WHAT YOU CAN DO

• Visualize success rate, depletion probability, asset longevity, and terminal wealth as a fan chart
• Enter your public pension (claiming age 60-75) and other regular income; income is deducted from required withdrawals
• Switch between four withdrawal strategies: fixed amount, fixed rate, dynamic guardrail, floor and ceiling
• Inverse analysis: solve the withdrawal amount that meets a target success rate (80-95%)
• Sensitivity analysis: sweep withdrawal rate, retirement age, and equity ratio
• Actuals tracking: log your total assets and compare reality with the plan
• Share your result as a single image (free)
• 3-question quick start gets you to your first result in seconds
• Siri Shortcuts to check your success rate or rerun the simulation

PREMIUM (one-time purchase, no subscription)

• Sequence-of-returns risk analysis, currency-hedge comparison, historical backtest
• Unlimited scenario saving and side-by-side comparison, PDF report export, higher simulation path counts

WHY MOCHIRU

• Built for JPY-based investors holding USD equities: it preserves the crash correlation where falling stocks and a strengthening yen hit your assets at the same time - a risk that simple "expected return plus risk" tools often miss

PRIVACY

• Calculations, inputs and records stay on your device and are never sent anywhere. The network is used only to buy or restore the purchase and to open the legal pages.

IN THIS VERSION

• Public pension (claiming age 60-75) and other regular income; income is applied first and only the shortfall is withdrawn
• Solver: find the annual amount you can spend for a target success rate (80-95%)
• Actuals tracking, one-image sharing (free), a three-question quick start and Siri Shortcuts
• All amounts are in Japanese yen (JPY). US equities are held in USD and converted to yen for the simulation
• The series used in "Historical" mode is a bundled sample (synthetic data), not real market data

NOTE

This app is a simulation for general information and learning purposes. It does not recommend specific financial products or advise on the timing of trades. Results are calculations based on the assumptions you enter and do not guarantee future investment performance.