Compound Interest vs WealthSim

See exactly what time and steady deposits do to your money. Enter a starting amount, a rate, a monthly deposit and the years you are willing to wait — the future value and a full growth chart redraw the instant you change any assumption. Most calculators stop at one number. This one runs an exact month-by-month simulation in decimal arithmetic: interest credited annually, semi-annually, quarterly or monthly; deposits at the start or end of the month; nominal rate and effective annual rate (APY) stated separately instead of quietly conflated; even negative rates handled without breaking. Then it lets you save each projection as a named scenario and lay two of them over each other on one chart. WHAT YOU GET • Your future balance in three honest numbers — final value, what you put in, and the interest time added — recalculated the instant you move a slider • A growth chart that separates your own deposits from compound growth, so you can spot the year interest starts outworking your paycheck • The real answer to "does monthly compounding matter?" — nominal rate and effective APY shown side by side on every projection • An "in today's money" toggle that restates your 30-year balance using your own inflation assumption — never a forecast we invented for you • Saved scenarios with names and colours — house deposit at 4.5%, index fund at 7% — each reopening exactly as you left it • Side-by-side comparison: two growth curves overlaid on one chart, with final balance, deposits and interest lined up underneath PERFECT FOR • Savers deciding whether the high-yield account or the index fund wins over the next 15 years • Parents starting a college fund who want to see what 150 a month actually becomes by graduation • Anyone negotiating with their future self — one more year of deposits, one chart to prove what it buys • Students learning why a 7% nominal rate is not a 7% effective rate, with numbers they chose themselves WHY NOT JUST A SPREADSHEET? A spreadsheet makes you build the formula yourself, and one wrong cell compounds the error — literally — over 600 monthly rows. This app simulates every month in exact decimal arithmetic, lands interest precisely on compounding boundaries, and reproduces the textbook formulas to the cent. You move a slider; it does the maths. PRIVATE BY DEFAULT Everything runs on your device. No account, no sign-up, and your numbers are never uploaded anywhere. Amounts display in your own currency and your keyboard's own decimal separator just works. FULL ACCESS Full Access unlocks unlimited saved scenarios and side-by-side scenario comparison. It is offered as an auto-renewing Weekly or Yearly subscription, or a one-time Lifetime purchase. Prices are shown in the app before you commit; subscriptions renew unless cancelled at least 24 hours before the current period ends and can be managed in your App Store account settings. Download Compound Interest Calculator and find out what your monthly deposit is really worth ten years from now. Terms of Use: https://leanstudio.asia/terms-of-use Privacy Policy: https://leanstudio.asia/privacy-policy Support: support@leanstudio.asia

How much will you have if you invest every month? WealthSim answers in one line, shows how much of it you put in and how much interest adds, and helps you stay on track month after month. The calculator, My plan and saved scenarios are free. CALCULATE • Starting amount, monthly contribution, years and expected return, with sliders or exact figures • Your result first: "In 2046 you'll have…", split into what you contribute and what interest adds • Yearly bars that mark the year interest overtakes your contributions • Fees and inflation, with the result in today's money • Illustrative return assumptions for 5, 10, 20 and 30 years • Contribute monthly, every two weeks or weekly, raise it a set percent each year, or add a one-off amount in any year • Export the year-by-year table as CSV, next to the image and PDF MY PLAN • Turn any projection into a goal with a target amount and date • Log your real balance each month and compare it with the route • If you fall behind, see how much extra per month brings you back • Coast FIRE: how much you need invested today to stop contributing and still reach your goal, and the month you can stop • A reminder on your contribution day and a monthly summary after each check-in: months ahead or behind, your streak and the next milestone • Free small Home Screen and Lock Screen widgets with your plan • Upcoming milestones and an optional monthly reminder SAVE AND SYNC • Save, search and reopen scenarios • Private iCloud sync across your devices, no account needed WEALTHSIM PRO • 100 futures: your plan replayed 10,000 times with real US market years since 1928, so you see how often you reach your goal and the bad, usual and good outcome • The harvest: how long a withdrawal lasts with a fixed amount, the 4% rule or guardrails that cut or raise spending • What if…? Try +50 or +100 a month or one or two more years before you change your plan • Compare up to three projections side by side • PDF report and clean images to share • Medium and large widgets: your real balance against the route, the arrival date and 100 futures, with a Log balance button • Shareable milestone cards without the WealthSim footer • Unlimited plans • No ads The free version shows ads. Pro is a one-time lifetime purchase, or an annual or monthly subscription. SUBSCRIPTIONS Payment is charged to your Apple Account at confirmation of purchase. Subscriptions renew automatically unless cancelled at least 24 hours before the end of the current period, and the renewal is charged within the 24 hours before it ends. Manage or cancel your subscription in your Apple Account settings. If you bought Remove Ads before, you keep an ad-free app. WealthSim projections and simulations are illustrations for educational purposes, not forecasts. They are not financial, investment, tax or legal advice. Actual returns, fees, inflation and losses may differ. Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/ Additional Terms: https://www.wealthsim.app/terms Privacy Policy: https://www.wealthsim.app/privacy Support: https://www.wealthsim.app/contact