# Annuity Calculator

URL: https://speedycalculator.com/calculators/finance/annuity/
Last updated: 2026-10-25

> The annuity calculator works out the future balance of regular deposits (or what remains after regular withdrawals) – with any payment frequency, ordinary or due timing, compounding, payment growth and starting balance – and the payment needed to reach a target.

## Inputs

- Payments are
- Starting balance
- Payment per period
- Annual interest rate (%)
- Number of years (years, months)
- Payment frequency
- Compounding frequency
- Payments made at
- Growth of payments per year (%)
- Target final balance

## Results

- Number of payments
- Final balance
- Total payments
- Total interest
- Deposit needed per period for the target

## Formula

```
Rate per period i = (1 + r ÷ m)^(m ÷ f) − 1
Final balance = B(1 + i)^n ± P × ((1 + i)^n − (1 + g)^n) ÷ (i − g) × (1 + i × timing)
Payment for a target = (target − B(1 + i)^n) ÷ annuity factor
```

## Explanation

An annuity is any series of equal (or steadily growing) payments. An ordinary annuity pays at the end of each period, an annuity due at the start – which earns one more period of interest.

### How to use the Annuity Calculator

- **Payments are**
- **Starting balance**
- **Payment per period**
- **Annual interest rate**
- **Number of years**
- **Payment frequency**
- **Compounding frequency**
- **Payments made at**
- **Growth of payments per year**
- **Target final balance**

Results update as you type, and every field accepts the units shown in its menu.

### How it works

Choose deposits or withdrawals, then enter the starting balance, payment, frequency, timing, length, rate, compounding, payment growth and an optional target.

### Tips

- Start early – time does more of the work than the amount you save.
- Take the full employer match if your plan offers one.
- Plan with a cautious return (4–6% after inflation) and check again every year.
- Know the contribution limits and required minimum distribution rules for your accounts.

### Common mistakes to avoid

- Ignoring inflation when setting a retirement target.
- Underestimating how long retirement can last.
- Withdrawing early and paying penalties and taxes.

### Inputs explained

FieldWhat to enterPayments areChoose one: Deposits, WithdrawalsStarting balanceAmount in your currencyPayment per periodAmount in your currencyAnnual interest rateIn %Number of yearsUnits: years, monthsPayment frequencyChoose one: Monthly, Semi-monthly, Bi-weekly, Weekly …Compounding frequencyChoose one: Yearly, Semi-annually, Quarterly, Monthly …Payments made atChoose one: End of each period, Beginning of each periodGrowth of payments per yearIn %Target final balanceAmount in your currency

### What each result means

- **Number of payments** = round([Number of years]×[Payment frequency])
- **Final balance** = [Starting balance]×(1 + [Rate per payment period])^[Number of payments] + [Payments are]×gfv([Rate per payment period], [Number of payments], [Payment per period], [Payment growth per period], [Payments made at])
- **Total interest** = [Final balance] - [Starting balance] - [Payments are]×[Total payments]
- **Deposit needed per period for the target** = max(([Target final balance] - [Starting balance]×(1 + [Rate per payment period])^[Number of payments])÷gfv([Rate per payment period], [Number of payments], 1, [Payment growth per period], [Payments made at]), 0)

### Example values

How the main result changes when **Starting balance** changes and everything else stays at the example values above:

Starting balanceFinal balance5,000155,163.297,500163,438.810,000171,714.3112,500179,989.8215,000188,265.3420,000204,816.36

## Worked example

Inputs — Payments are: Deposits; Starting balance: $10,000; Payment per period: $300; Annual interest rate: 6 %; Number of years: 20 years; Payment frequency: Monthly; Compounding frequency: Monthly; Payments made at: End of each period; Growth of payments per year: 0 %; Target final balance: $250,000.

Results — Number of payments = 240; **Final balance = $171,714.31**; Total payments = $72,000.00; Total interest = $89,714.31; Deposit needed per period for the target = $469.43.

## FAQ

**What is an annuity?**
A series of equal payments at regular intervals.

**What is the difference between an ordinary annuity and an annuity due?**
Ordinary pays at the end of each period; due pays at the start.

**Is this the same as an insurance annuity?**
The maths is the same; insurance annuities add fees and guarantees.

**What formula does the Annuity Calculator use?**
Rate per period i = (1 + r ÷ m)^(m ÷ f) − 1.


## Sources

- [U.S. SEC – Investor.gov compound interest and investing basics](https://www.investor.gov/)