CompoundFX: Compound Interest

Investment Finance Calculator

Only for iPhone

Free · In‑App Purchases

iPhone

Stop using basic calculators that ignore reality. CompoundFX models true investment growth by letting you easily factor in expense ratios, tax drag, and inflation. CompoundFX is the compound interest calculator that shows you what it takes, not just what you'll have. Model investment growth, plan for retirement, and pressure-test your FIRE goals with precision. Set a goal, $1M by age 60, a down payment, or a college fund, and CompoundFX solves for the missing piece. The rate you’ll need. The years it will take. The deposit you have to make. No more guessing. No more trial and error. GOAL MODE Pick your goal. Choose what to solve for. CompoundFX does the financial math. - Solve for Rate of Return - Solve for Time Horizon - Solve for Starting Principal - Solve for Monthly Contribution COMPARE SCENARIOS Should you save more or invest longer? Pay off debt or boost your 401(k)? Save scenarios and put them head-to-head. See the difference, the total dollar impact, and exactly when one strategy pulls ahead. A CALCULATOR THAT SHOWS ITS WORK - Real-time growth chart with milestone markers ($100K, $250K, $1M) - Year-by-year breakdown with full transparency - Inflation, Taxes, and Expense Ratios: See what you actually keep after fee drag - Daily, weekly, monthly, or annual contributions - Custom compounding intervals (Daily to Annually) - Sub-year precision for short-horizon plans DESIGNED FOR iPHONE & INDIE DEV Dark glass UI. Smooth haptics. Built natively in SwiftUI for iOS 17 and up. No accounts. No ads. No tracking. Your scenarios stay locally on your device. EXPORT AND SHARE Generate a polished two-page PDF report with an executive summary, growth chart, and full milestone breakdown. Or share a branded image to text or social media. FREE FEATURES - Full compound interest calculator - Real-time growth chart and year-by-year table - Inflation, tax, and expense adjustments - Custom contribution and compounding schedules - Branded image sharing PRO: $4.99 (ONE-TIME PURCHASE) - Goal Mode (Solve for any missing variable) - Save unlimited scenarios - Compare scenarios side-by-side - Export two-page PDF reports One purchase. Unlocked forever. Family Sharing fully supported. WHO IT'S FOR Whether you're starting your first Roth IRA, managing index funds, planning early retirement, modeling a college fund, or tracking a Bogleheads portfolio, CompoundFX gives you the answer in seconds. PRIVACY FIRST CompoundFX is fully offline. No data collection. No accounts required. No analytics. No third-party SDKs. Your personal finance data is stored safely on your device. DISCLAIMER CompoundFX is for educational and planning purposes. It does not provide investment, tax, or financial advice. Returns shown are projections based on the inputs you provide and do not guarantee actual investment performance. Questions or feedback? support@originsoftware.net

  • This app hasn’t received enough ratings or reviews to display an overview.

What's New in CompoundFX 1.2 More accurate Goal Mode • Tax-aware solving: Goal Mode now fully accounts for annual tax treatment when solving for rate, duration, principal, or deposit. Your solved values land exactly on target. Settings that respond instantly • Live tax treatment: Switching between Annual and Deferred tax treatment now updates your current scenario immediately. There's no need to start a new scenario to see the change. Refined calculations • Smarter tax modeling: Tax is no longer applied against negative returns in high-fee, low-return scenarios, keeping after-tax projections conservative and correct. • Consistent formatting: Currency displays are now locked to a consistent format on every device, regardless of region settings. Under the hood • Snappier response: Rate of Return now recalculates dramatically faster while you adjust sliders. Thank you for your support and feedback! If you're loving the app, please consider leaving a review.

The developer, Origin Software, Inc., 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 Not Collected

    The developer does not collect any data from this app.

    Privacy practices may vary, for example, based on the features you use or your age. Learn More

    The developer has not yet indicated which accessibility features this app supports. Learn More

    Seller
    • Origin Software, Inc.
    Size
    • 4.5 MB
    Category
    • Finance
    Compatibility
    Requires iOS 17.0 or later.
    • iPhone
      Requires iOS 17.0 or later.
    Languages
    • English
    Age Rating
    4+
    In-App Purchases
    Yes
    Copyright
    • © 2026 Origin Software, Inc.