How to Calculate a Tip
Learn how to calculate a tip quickly using a simple percentage formula. See how to calculate the tip amount, total bill, split the bill between multiple people, and handle common tip percentages such as 15%, 18%, 20%, and 25%.
Money & Math
ToolCMB Team
Updated
1 min read
How to Calculate Your Monthly Mortgage Payment
The mortgage formula in plain English, a worked example and the four numbers that change your payment the most.
ToolCMB Team
Updated
1 min read
On this page
The formula
The standard monthly payment formula is M = P × r(1+r)n / ((1+r)n − 1), where P is the loan amount, r is the monthly interest rate and n is the number of payments.
Worked example
For a $300,000 loan at 6% for 30 years: r = 0.005 and n = 360, which gives a monthly principal and interest payment of about $1,799.
What changes your payment
- Loan amount (price minus down payment)
- Interest rate
- Loan term (15 vs 30 years)
- Property tax, insurance and HOA fees
Skip the math with our free Mortgage Calculator.
This article is for information only and is not financial advice.
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