Compound Wealth Simulator
FIRE • Real Returns • Compare
Only for iPhone
Free · Designed for iPhone. Not verified for macOS.
iPhone
Inflation-aware real returns. Reverse-calc contributions from your goal. Compare 3 yield scenarios. 23 currencies, 7 languages. For FIRE, IRA & 401(k) planning.
Compound Interest Calculator helps you visualize long-term investments with realistic, inflation-adjusted projections.
Reverse-calculate from your savings goal, set independent contribution and growth periods, and plan with confidence for FIRE, retirement, or
any long-term financial milestone.
■ Who this is for
- Anyone planning long-term investments (IRA, Roth IRA, 401(k), ISA, NISA, iDeCo)
- The FIRE community
- Retirement planners
- Goal-based savers
- Inflation-conscious investors
■ 3 Calculation Modes
- Calculate — Future value from initial assets and contributions
- Reverse — Required monthly contribution to reach your goal
- Compare — 3 return scenarios side by side
■ Independent Contribution Period
Set your contribution years separately from your overall growth period (e.g. contribute for the first 10 years of a 30-year horizon, then
let the balance compound). The chart highlights when contributions stop with a visual marker.
■ "Time to Goal" Reverse Calculation
Calculate how long it takes to reach your target as "X years Y months." Just enter your monthly contribution and assumed return rate.
■ Inflation-Aware
Display both nominal and real (purchasing-power) returns. Especially useful for users in high-inflation economies who want to understand the
true future value of their savings.
■ 23 Currencies, 7 Languages
Major world currencies including USD, EUR, GBP, JPY, CNY, KRW, INR, BRL, MXN, TRY. UI in English, Japanese, Chinese, Korean, Hindi, Spanish,
and Portuguese.
■ Locale-Aware Number Formatting
- Japan / China — 万, 億, 兆
- India — Lakh, Crore
- English-speaking — K, M, B, T
Numbers display in the format locals naturally read.
■ Privacy & Ads
- All calculations happen on-device. Your input data is never sent to our servers.
- This app is free, supported by in-app advertising.
■ Technical
- iOS 15.6 or later
- iPhone only
■ Disclaimer
Calculations are simulations and do not guarantee future investment performance or inflation rates. Investment decisions are your own
responsibility.
Ratings & Reviews
- This app hasn’t received enough ratings or reviews to display an overview.
・Fixed an issue where the default inflation rate for some currencies was not reflected on the slider.
・Improved compound interest accuracy when the contribution period is set to 0 years.
・Other minor visual refinements and UI improvements.
The developer, Kyohei Hayakawa, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Used to Track You
The following data may be used to track you across apps and websites owned by other companies:
- Identifiers
- Usage Data
Data Linked to You
The following data may be collected and linked to your identity:
- Location
- Identifiers
- Usage Data
Data Not Linked to You
The following data may be collected but it is not linked to your identity:
- Diagnostics
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Kyohei Hayakawa
- Size
- 8.4 MB
- Category
- Finance
- Compatibility
Requires iOS 15.6 or later.
- iPhone
Requires iOS 15.6 or later. - iPod touch
Requires iOS 15.6 or later. - Mac
Requires macOS 12.5 or later and a Mac with Apple M1 chip or later. - Apple Vision
Requires visionOS 1.0 or later.
- iPhone
- Languages
English and 6 more
- English, Hindi, Japanese, Korean, Portuguese, Simplified Chinese, Spanish
- Age Rating
4+
- 4+
- Contains
Advertising
- Copyright
- © 2026 Kyohei Hayakawa