Mortgage loans require careful planning. Use this single-file tool to quickly estimate your monthly payments, loan principal, or repayment term, mirroring the functionality needed for complex financial modeling in Google Sheets.
Mortgage Calculator for Google Sheets
Calculated Result:
Calculation Steps
Mortgage Calculator for Google Sheets Formula
The standard formula used for calculating the monthly mortgage payment (M) is essential for financial modeling and is used by tools like the `PMT` function in Google Sheets.
$$M = P \left[ \frac{i (1 + i)^n}{(1 + i)^n – 1} \right]$$
Where $P$ is the principal, $i$ is the monthly interest rate, and $n$ is the total number of payments (months).
Formula Source: Investopedia | Bankrate
Variables
A quick explanation of the key variables in the calculator module:
- Loan Principal ($): The initial amount borrowed from the lender. This is the starting balance of the loan.
- Annual Interest Rate (%): The yearly rate charged on the loan balance. It is converted to a monthly rate for calculations.
- Loan Term (Years): The number of years over which the loan is scheduled to be repaid. This is converted into total months ($n$).
- Optional Monthly Payment ($): If you know your target payment, you can input it here and solve for the required Principal or Term.
Related Calculators
Explore other financial modeling tools for managing debt and investments:
- Amortization Schedule Planner
- Loan Refinancing Comparison Tool
- Total Interest Paid Calculator
- Debt-to-Income Ratio Estimator
What is Mortgage Calculator for Google Sheets?
A “mortgage calculator for Google Sheets” refers to the financial model or formula set up within a spreadsheet application that replicates the complex amortization process. This allows users to not only find a single payment result but also to play with assumptions, create full amortization tables, and integrate the loan data with other personal financial projections within the flexible Google Sheets environment.
While simple online calculators give you a final number, the ability to build and adjust the model in Google Sheets—often using functions like `PMT`, `IPMT`, and `PPMT`—provides unparalleled control and transparency. Our calculator uses the same core mathematical principles as these spreadsheet functions to ensure consistency and accuracy when validating your Sheets model.
How to Calculate Mortgage for Google Sheets (Example)
Here is a step-by-step example of calculating the monthly payment for a 30-year, $200,000 loan at 5% annual interest.
- Determine the Monthly Rate ($i$): Divide the Annual Rate by 12 and 100. (5% / 100) / 12 = 0.004167.
- Determine Total Payments ($n$): Multiply the Loan Term in years by 12. 30 years * 12 months/year = 360 payments.
- Calculate the Compounding Factor: $(1 + i)^n = (1.004167)^{360} \approx 4.4677$.
- Calculate the Payment Factor: Divide $i \cdot (1+i)^n$ by $((1+i)^n – 1)$. $0.004167 \cdot 4.4677 / (4.4677 – 1) \approx 0.005368$.
- Find the Monthly Payment (M): Multiply the Principal ($P$) by the Payment Factor. $\$200,000 \times 0.005368 \approx \$1,073.64$.
Frequently Asked Questions (FAQ)
Is the `PMT` function in Google Sheets the same as this calculator?
Yes, the mathematical formula used here is the core logic behind the Google Sheets `PMT` function. Both use the loan principal, interest rate (per period), and number of periods to determine the required payment.
What is the difference between Annual Rate and Monthly Rate?
The Annual Interest Rate is the stated yearly rate (e.g., 6%). The Monthly Rate is the annual rate divided by 12. All mortgage payment calculations use the Monthly Rate ($i$).
Why is my calculation result slightly off from my bank statement?
The slight differences are usually due to rounding, private mortgage insurance (PMI), property taxes, or homeowners insurance (PITI) being bundled into your actual bank payment. This calculator provides the principal and interest portion only.
Can I use this calculator to solve for the loan term?
Yes, if you input the desired Monthly Payment, the calculator will solve for the required Loan Term (in years) needed to repay the loan at that specific payment amount.