If you’ve tuned into tech news, you’ve likely heard about DeepSeek, the AI tool rapidly becoming the powerhouse for web developers and creative professionals. I decided to handover a common request from real estate agents to DeepSeek:

“Can you add a mortgage calculator that actually follows Canadian rules?”

What Is DeepSeek R1?

DeepSeek R1 is a specialized AI assistant designed for technical precision in regulated industries like finance and real estate. Unlike general-purpose models such as OpenAI’s ChatGPT or Google’s Gemini, DeepSeek R1 combines coding expertise with domain-specific knowledge, making it uniquely suited for tasks like Canadian mortgage calculations.

The Prompt

To create a Canadian mortgage calculator with CMHC insurance, semi-annual compounding, and mobile-friendly design, I used this single prompt in DeepSeek R1:

Create a Canadian mortgage calculator in one HTML file with:  
1. Home price input ($)  
2. Toggle between down payment %/$, defaults to 20%
3. Input field for interest rate, defaults to 5% 
4. Selectable dropdown for payment frequency, defaults to Monthly
5. Auto-CMHC insurance for < 20% down  
6. 5–30 year amortization slider  
7. Semi-annual compounding formula  
8. Mobile-responsive design (hex: #5e81ac)  
9. Error handling for invalid inputs  
10. Total interest and payment breakdown  
11. Show dollar amounts with decimal and thousands separators
Include all CSS/JS in one file.  

The Result

DeepSeek R1 then proceed to take 17 seconds and generated the code:

1. Core Features:
   • Toggleable down payment input (Percentage % or Dollar Amount $), defaulted to 20%
   • Interest rate input, defaulted to 5%
   • Payment frequency selector (Monthly, Semi-Monthly, Bi-Weekly, Weekly)
   • 5 – 30 year amortization slider
   • Auto-CMHC insurance calculation for < 20% down payments
2. Financial Calculations:
   • Semi-annual compounding interest formula
   • CMHC insurance rates based on down payment percentage
   • Payment amount calculation for different frequencies
   • Total interest and cost calculations
3. User Experience:
   • Mobile-responsive design with site brand color
   • Real-time calculations as users input values
   • Error handling for invalid inputs
   • Currency formatting with thousands separators

The Final Product

I ran some test numbers, and then compared the results with the Mortgage Calculator on REALTOR.ca:

The DeepSeek R1 generated mortgage calculator was able to formulate the same monthly mortgage amount as the mortgage calculator from REALTOR.ca.

While a professional web designer would need to customize the tool to better fit into your real estate branding, leveraging an AI tool can save a web developer or a more technical real estate agent hours of coding to put a mortgage calculator on your website.

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You can try the live demo here: