---
title: "Compound Interest Calculator: Free Online Tool & FAQs | ShoutingNow"
description: Enter your starting balance, interest rate, compounding frequency, and time horizon. Add optional regular deposits to see future value, total interest, APY.
url: "https://shoutingnow.com/tools/compound-interest-calculator/"
image: "https://shoutingnow.com/wp-content/uploads/2026/07/shoutingnow-preview-scaled.webp"
---

# Compound Interest Calculator

Put in a starting balance, interest rate, how often it compounds, and how long you plan to leave the money alone. Add regular deposits or withdrawals if you use them, then read future value, total interest, APY, and the period breakdown.

## How to use this compound interest calculator

1. Enter your starting balance and the annual interest rate as a percent.
2. Choose how often interest compounds (yearly, monthly, daily, and so on) and how many years to project.
3. Optional: add recurring deposits or withdrawals, including how often they happen and any annual increase.
4. Click Calculate to see future value, interest earned, APY, doubling time, the breakdown table, and the chart. Use Save if you want to keep the run in this browser.

This page projects a balance over time. If you only need to convert one quoted rate into another compounding basis, use a dedicated rate tool or the APY fields on a savings or CD page instead.

## What is compound interest?

Compound interest pays you on the original principal and on interest that already landed in the account. Each compounding period raises the balance, so the next period runs the rate on a larger number. That is why savings accounts, bonds, and loans usually show both a nominal rate and an effective annual yield.

### Periodic compounding formula

If interest compounds *n* times a year for *t* years at nominal rate *r*, a starting balance *A0* grows like this when you leave it alone:

Regular deposits and withdrawals change the path. The calculator steps through each period so those cash flows show up in the table and chart, not only in a closed-form lump-sum formula.

### Continuous compounding

If you shrink the compounding gap toward zero, the balance approaches this continuous model:

### Rule of 72

A rough mental shortcut for doubling time at a steady annual rate:

At 6% a year, money doubles in about 72 ÷ 6 ≈ 12 years. Treat that as a napkin estimate. Use the full projection when the answer matters.

### Compounding frequency reference

FrequencyPeriods per yearTypical use

Annually1Some bonds and annual statements
Quarterly4Dividends and certain deposits
Monthly12Many savings and loan quotes
Biweekly26Payroll-linked savings
Daily365High-yield savings marketing
Continuously∞Theoretical upper bound for a given nominal rate

### Why APY and APR disagree

A 6% nominal rate compounded monthly is not the same as 6% paid once a year. Twelve months of 0.5% on a growing balance lands near a **6.17% effective annual yield**. Banks and lenders pick the figure that suits the pitch, so comparing APYs (or running both through this calculator) keeps the comparison honest.

## Examples and use cases

### Worked example

Start with **$10,000** at **6% compounded monthly** for **5 years**, with no extra deposits:

- Monthly rate = 6% ÷ 12 = 0.5%
- Ending balance ≈ $13,488 before fees or taxes
- Effective yield ≈ 6.17% APY

Add a monthly deposit and the ending balance jumps further. The table shows how much of that growth came from contributions versus interest.

### Where people use this

- Savings goals: See whether a high-yield account plus monthly transfers reaches a target by a date you care about.
- Emergency fund planning: Test a conservative rate and a more optimistic one without rebuilding the spreadsheet.
- Comparing offers: Plug two APYs and contribution plans side by side before you move money.
- CD hold periods: For a certificate with a fixed term and no monthly deposits, also try the CD Calculator for maturity-focused outputs.

## Frequently Asked Questions

### What is the difference between APR and APY?
**APR** is usually a nominal rate quoted without spelling out every compounding effect. **APY** is the effective yearly return after compounding. This calculator shows both so you can see how much the frequency changes the outcome.

### Why does 6% monthly look like about 6.17% annually?
Each month you earn 0.5% on a balance that already grew last month. Do that twelve times and you get (1 + 0.06/12)12 − 1 ≈ 6.17% for the year.

### Can I include monthly deposits or withdrawals?
Yes. Choose deposits or withdrawals, set the amount and frequency, and optionally raise that contribution each year. The chart and table include those cash flows.

### What does continuous compounding mean?
It is the limit case where interest is applied in infinitely small steps. For a given nominal rate it is the mathematical ceiling, modeled with *e*rt. Most consumer accounts compound daily or monthly instead.

### Does compounding frequency really change much?
It does, especially over longer terms or with larger balances. Switch between annual, monthly, daily, and continuous on the same inputs to see how wide the gap gets.

### Are taxes and fees included?
No. Results are pre-tax and ignore account fees. Treat them as a planning estimate, then adjust for your tax situation and any product costs.

```json
[{"@context":"https://schema.org","@type":"Organization","name":"ShoutingNow","url":"https://shoutingnow.com/","logo":{"@type":"ImageObject","url":"https://shoutingnow.com/wp-content/themes/shoutingnow-theme/assets/images/logo.png"},"sameAs":["https://x.com/makani20","https://www.linkedin.com/in/makani20/","https://post-see.com"],"contactPoint":{"@type":"ContactPoint","contactType":"customer support","email":"support@shoutingnow.com","url":"https://shoutingnow.com/contact/"},"slogan":"Learn. Build. Grow."},{"@context":"https://schema.org","@type":"WebPage","name":"Compound Interest Calculator","description":"Enter your starting balance, interest rate, compounding frequency, and time horizon. Add optional regular deposits to see future value, total interest, APY.","url":"https://shoutingnow.com/tools/compound-interest-calculator/","inLanguage":"en-US"},{"@context":"https://schema.org","@type":"SoftwareApplication","name":"Compound Interest Calculator","description":"Enter your starting balance, interest rate, compounding frequency, and time horizon. Add optional regular deposits to see future value, total interest, APY.","applicationCategory":"UtilitiesApplication","operatingSystem":"Web","url":"https://shoutingnow.com/tools/compound-interest-calculator/","isAccessibleForFree":true,"offers":{"@type":"Offer","price":0,"priceCurrency":"USD","availability":"https://schema.org/InStock","url":"https://shoutingnow.com/tools/compound-interest-calculator/"},"provider":{"@type":"Organization","name":"ShoutingNow","url":"https://shoutingnow.com/","logo":{"@type":"ImageObject","url":"https://shoutingnow.com/wp-content/themes/shoutingnow-theme/assets/images/logo.png"},"sameAs":["https://x.com/makani20","https://www.linkedin.com/in/makani20/","https://post-see.com"],"contactPoint":{"@type":"ContactPoint","contactType":"customer support","email":"support@shoutingnow.com","url":"https://shoutingnow.com/contact/"}}},{"@context":"https://schema.org","@type":"HowTo","name":"How to use Compound Interest Calculator","description":"Enter your starting balance, interest rate, compounding frequency, and time horizon. Add optional regular deposits to see future value, total interest, APY.","url":"https://shoutingnow.com/tools/compound-interest-calculator/","inLanguage":"en-US","step":[{"@type":"HowToStep","name":"starting balance","text":"Enter your starting balance and the annual interest rate as a percent."},{"@type":"HowToStep","name":"compounds","text":"Choose how often interest compounds (yearly, monthly, daily, and so on) and how many years to project."},{"@type":"HowToStep","name":"deposits","text":"Optional: add recurring deposits or withdrawals, including how often they happen and any annual increase."},{"@type":"HowToStep","name":"Calculate","text":"Click Calculate to see future value, interest earned, APY, doubling time, the breakdown table, and the chart. Use Save if you want to keep the run in this browser."}]},{"@context":"https://schema.org","@type":"FAQPage","mainEntity":[{"@type":"Question","name":"What is the difference between APR and APY?","acceptedAnswer":{"@type":"Answer","text":"APR is usually a nominal rate quoted without spelling out every compounding effect. APY is the effective yearly return after compounding. This calculator shows both so you can see how much the frequency changes the outcome."}},{"@type":"Question","name":"Why does 6% monthly look like about 6.17% annually?","acceptedAnswer":{"@type":"Answer","text":"Each month you earn 0.5% on a balance that already grew last month. Do that twelve times and you get (1 + 0.06/12)12 − 1 ≈ 6.17% for the year."}},{"@type":"Question","name":"Can I include monthly deposits or withdrawals?","acceptedAnswer":{"@type":"Answer","text":"Yes. Choose deposits or withdrawals, set the amount and frequency, and optionally raise that contribution each year. The chart and table include those cash flows."}},{"@type":"Question","name":"What does continuous compounding mean?","acceptedAnswer":{"@type":"Answer","text":"It is the limit case where interest is applied in infinitely small steps. For a given nominal rate it is the mathematical ceiling, modeled with ert. Most consumer accounts compound daily or monthly instead."}},{"@type":"Question","name":"Does compounding frequency really change much?","acceptedAnswer":{"@type":"Answer","text":"It does, especially over longer terms or with larger balances. Switch between annual, monthly, daily, and continuous on the same inputs to see how wide the gap gets."}},{"@type":"Question","name":"Are taxes and fees included?","acceptedAnswer":{"@type":"Answer","text":"No. Results are pre-tax and ignore account fees. Treat them as a planning estimate, then adjust for your tax situation and any product costs."}}]},{"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"ShoutingNow","item":"https://shoutingnow.com/"},{"@type":"ListItem","position":2,"name":"Tools","item":"https://shoutingnow.com/tools/"},{"@type":"ListItem","position":3,"name":"Compound Interest Calculator","item":"https://shoutingnow.com/tools/compound-interest-calculator/"}]}]
```