Show Borrowers When a Mortgage Quote Costs Too Much
The person quoting the loan is selling the loan. Give borrowers an independent comparison across 3,700+ credit unions, with source evidence and no paid placement.
What is Rate Shopping with RateAPI?
This use case is specifically about comparing a borrower's mortgage quote against independent alternatives. RateAPI's decisions endpoint accepts a current offer (rate, APR, state, loan amount) and returns where it ranks against 3,700+ credit unions, plus estimated savings from better options. One API call replaces thousands of individual website visits. Unlike affiliate sites, results are ranked by true cost—not advertising revenue.
Related: live mortgage rates, national rate benchmark, and how we collect data.
Users Can't Tell If Their Quote Is Competitive
A homebuyer gets a mortgage quote and hears that it is "competitive." But the person presenting that rate usually benefits when the borrower accepts it. That does not make the quote dishonest; it means the quote is an offer, not an independent search of the market.
Better-fitting offers may be available from credit unions the buyer has never heard of. Without comparable APRs, points, fees, eligibility details, and source evidence, the borrower cannot tell whether switching lenders is worth the effort.
Your app can change this. With one API call, show users exactly where their quote ranks against 3,700+ credit unions—and how much they could save by shopping around.
One API Call, Complete Market Intelligence
// Get mortgage recommendations for CaliforniaPOST /v1/decisions { "decision_type": "financing", "context": { "geo": { "state": "CA" } }, "product_request": { "product_type": "mortgage", "amount": 500000, "term_months": 360, "intent": "purchase" }, "current_offer": { "rate": 6.75, "apr": 6.89 }}{ "summary": { "recommended_action": "shop_providers", "confidence": 0.92, "current_offer_rank": 847, "total_providers_analyzed": 1203, "estimated_savings": { "monthly": 187, "total": 67320 } }, "actions": [{ "offers": [ { "rank": 1, "credit_union_name": "Navy Federal Credit Union", "apr": 6.125, "monthly_payment": 3038, "estimated_monthly_savings": 187 }, // ... more offers ] }]}Built for Rate Comparison
Instant Market Benchmarking
One API call returns ranked recommendations by true cost—APR, points, and fees. Show users exactly where their quote stands across RateAPI's independent institution coverage.
3,700+ Credit Union Coverage
Surface institutions borrowers may never discover on their own, with no paid placement deciding which lender appears first.
Transparent Savings Calculations
Every recommendation includes monthly payment and total interest savings. Users see real dollar impact, not abstract rate differences.
Daily Updates with Evidence
Daily updates via automated scraping. Every rate includes a timestamp so users know exactly when it was observed.
True Cost Ranking
Lower advertised rates sometimes rank below higher ones when fees make them more expensive. We rank by what users will actually pay, not headline APR.
Who Uses Mortgage Comparison APIs
Real Estate Platforms
Show estimated monthly payments with live rates next to property listings.
Mortgage Brokers
Give clients transparent market data to build trust and close deals faster.
Financial Advisors
Help clients optimize their largest liability with data-driven recommendations.
Data You Can Trust
Zero Affiliate Relationships
Zero affiliate relationships means zero incentive to promote specific lenders. We rank purely by what's best for users.
Source URL Verification
Every rate links back to the original source page. Users can verify any data point themselves.
Published Methodology
Our data collection and normalization process is fully documented. No black boxes.
No Lead Selling
We never sell user data or inquiries to lenders. Your users' privacy stays protected.
Explore Rates in the Live CLI Demo
Run our rate explorer locally to see exactly what data is available. Filter by state, product type, and see ranked recommendations instantly.
# Clone and run the rate explorer demogit clone https://github.com/rate-api/demoscd demos/rate-explorernpm installnode rate-explorer.js --state CA --amount 500000Frequently Asked Questions
Common questions about rate shopping with RateAPI
How does the decisions endpoint work?
The decisions endpoint accepts a user's current offer (rate, APR, state, loan amount) and returns ranked alternatives from 3,700+ credit unions. It calculates where the current offer ranks, estimates potential savings, and provides actionable recommendations. One API call replaces manual comparison across thousands of lender websites.
What data do I need to compare rates?
To compare rates, you need the user's state (2-letter code), loan amount, loan intent (purchase or refinance), and optionally their current quoted rate and APR. The API uses this context to return relevant offers ranked by true cost, including monthly payment and total interest savings calculations.
How are savings calculated?
Savings are calculated by comparing the user's current offer against better alternatives. The API computes monthly payment differences and total interest savings over the loan term. For example, a 0.5% rate reduction on a $500,000 loan can save over $50,000 in total interest over 30 years.
Why is RateAPI different from affiliate rate sites?
Unlike affiliate sites that rank by advertising revenue, RateAPI ranks offers by true cost—APR, points, and fees combined. We have zero affiliate relationships, so there's no incentive to promote specific lenders. Results reflect what's genuinely best for users, not who paid the most for placement.
How fresh is the rate data?
Rate data is updated daily through automated scraping of 3,700+ credit union websites. Every rate includes a timestamp showing when it was last observed. This ensures users see current market conditions, not stale data from weeks or months ago.
How do I add mortgage rate comparison to my app?
Get a free RateAPI key, then POST a user's state, loan amount, intent, and current offer to the /v1/decisions endpoint. It returns ranked alternatives from 3,700+ credit unions with monthly payment and total interest savings. The free tier includes 20 requests/month (email required).
Can I use RateAPI for products other than mortgages?
Yes. This page focuses on mortgage shopping, but RateAPI also covers auto, RV, boat, motorcycle, powersports, HELOC, personal, student, and equipment loans; credit cards; savings and money market accounts; and CDs and IRA CDs. Product-specific endpoints and decision tools help apps compare the relevant terms for each category.
Ready to Add Rate Comparison to Your App?
Get your API key in seconds. Free tier includes 20 requests/month (email required). No signup form, no sales calls.