Construction Loan Calculator: Estimate Your Building Loan with Ease
Use our free Construction Loan Calculator to find your monthly interest-only payments, total interest during construction, and post-construction mortgage estimates — perfect for home builders, investors, and land developers.
Construction Loan Calculator
Calculate your construction loan costs and payments
Your Loan Results
What Is a Construction Loan Calculator?
A Construction Loan Calculator helps you estimate the financial aspects of building a home or commercial property. Whether you’re planning a new residential project or seeking a commercial construction loan calculator, this tool simplifies complex financial decisions by providing monthly interest-only payments and mortgage estimates once the building is complete.
This calculator is ideal for:
Homeowners building on a plot of land
Investors considering construction to permanent loan calculators
Builders and developers managing costs
Users wondering how to calculate construction loan interest
Try it now to get clarity before breaking ground.
How to Use Our Construction Loan Payment Calculator?
Using the calculator is simple:
Enter the total loan amount.
Add your estimated construction period (in months).
Input the annual interest rate.
Specify your down payment percentage.
Select your mortgage term after construction (15 or 30 years).
Add the post-construction mortgage interest rate.
Choose whether it’s a purchase or refinance.
Then, click Calculate to get:
Monthly interest-only payments during construction
Total construction interest
Estimated post-construction monthly payments
Total loan cost
💡 Pro Tip: You can also explore our Land Loan Calculator to estimate costs before construction begins.
✅ Understanding Construction-to-Permanent Loan Calculations
A construction to permanent loan calculator works in two phases:
Phase 1: During construction, you typically make interest-only payments based on the disbursed amount.
Phase 2: Once construction is complete, the loan converts to a regular mortgage, and you pay principal + interest.
Our calculator handles both parts, making it easier for you to budget ahead.
✅ How Do You Calculate Interest on a Construction Loan?
To calculate construction loan interest manually:
Determine the average outstanding loan balance during construction.
Multiply by the annual interest rate.
Divide by 12 for monthly interest payments.
This process can be tedious, especially when funds are drawn over time.
✅ How to Use a Land Construction Calculator Before Building?
Before applying for a construction loan, it’s wise to estimate land-related expenses. Use our Land Loan Calculator to:
Estimate land loan payments
Calculate interest-only land loans
Decide between land-only vs construction loans
This step ensures you understand the full cost from land purchase to move-in.
✅ Related Calculators
Rent vs Sell Calculator – Decide whether to rent your property or sell it
Land Contract Calculator – Ideal for owner-financing situations.
✅ FAQ – Construction Loan Calculator
❓ What is a construction loan calculator?
A construction loan calculator helps estimate interest-only payments during the building phase and future mortgage payments after construction.
❓ How do you calculate a construction loan payment?
You calculate it based on the loan amount, construction duration, interest rate, and mortgage terms. Our calculator does all this for you.
❓ Can I use this calculator for a commercial property?
Yes, it also serves as a commercial construction loan calculator for small developers or commercial builds.
❓ What is a construction-to-permanent loan?
This type of loan converts from a construction loan to a mortgage once the building is finished. It saves you from applying for two loans.
❓ Is this calculator mobile-friendly?
Yes! It’s built to be fully responsive and works perfectly on phones and tablets.