Annuity Calculator
Find annual and monthly payouts from a principal over N years.
🏦 Annuity: how much you can withdraw yearly so the money lasts exactly N years. Common for retirement planning.
What Is This Tool?
An annuity pays out a fixed amount regularly from a principal over a set period. This calculator finds the annual and monthly payout that exhausts the principal in exactly N years, accounting for investment growth.
The Annuity Formula
Annual payout = P × r / (1 − (1 + r)^−n), where P is principal, r is annual rate, and n is years. The formula ensures the balance hits zero exactly at year n.
Annuity vs. Perpetuity
An annuity pays out for a fixed term. A perpetuity pays forever (the "4% rule" for retirement is roughly a perpetuity designed to never run out). For very long horizons (30+ years), the two converge.
Real-World Uses
- Retirement drawdown planning
- Lottery payout decisions (lump sum vs. annuity)
- Pension and structured settlement evaluation
- Charitable gift annuities
Frequently Asked Questions
What if I live longer than N years?
Then the annuity is exhausted. This is the core risk of self-managed drawdowns. Commercial annuities from insurance companies often pay for life, but at lower rates because they pool longevity risk.
About the Annuity Calculator
The Annuity Calculator lets you figure out annuity calculatorinstantly, without reaching for a spreadsheet or doing the math by hand. Whether you're planning a budget, checking a loan, or working through homework, the tool applies the correct formula behind the scenes and shows the result the moment you enter your numbers.
Unlike a static chart or table, this calculator adapts to your exact inputs. You can adjust any value and see the outcome update in real time, which makes it easy to compare scenarios — for example, "what if the rate were 1% lower?" or "what if I paid an extra $50 a month?"
How to Use This Tool
- Enter the main values the calculator asks for (for example, amount, rate, and time).
- Pick the right unit or option where the tool offers a choice.
- Read the result, which appears instantly below the inputs.
- Adjust any field to test a different scenario — the answer updates without a reload.
- Copy or note the result. Nothing is stored, so close the tab when you're done.
Why Use an Online Calculator?
Browser-based tools like this one have a few real advantages over installed software or manual methods:
- No installation. It opens instantly in any browser, on any operating system.
- Private by default. Everything runs locally, so your data stays on your device.
- Always up to date.There's nothing to update — you always get the latest version when you load the page.
- Free and unlimited. Use it as often as you like, with no account and no caps.
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