What this number is — and isn't
Freddie Mac's Primary Mortgage Market Survey polls lenders weekly on the rate offered to strong borrowers (good credit, 20% down) on conforming 30- and 15-year loans. It's the industry's reference number — but it's an average of offers, not a quote: your rate moves with your credit score, points, property type, and lender competition. Use it as the baseline the quotes you receive should be measured against.
Using it
Rate shopping? Put this week's number and your quotes through the mortgage calculator to see the payment difference. Already own? If this page's number sits meaningfully below your rate, the refinance calculator computes your break-even, and the Mortgage Lab lets you stack the refinance with everything else you're planning.
Put this on your own site
The current rates are available as a small embeddable badge — one iframe tag, auto-updating, no tracking. Get the embed code.
Data
Source: Freddie Mac Primary Mortgage Market Survey, published every Thursday. Our server fetches it directly from Freddie Mac and caches it briefly; your browser talks only to us.