So I was looking back at the mortgage interest rates from July 2023, and it's pretty interesting to see where things were at that time. The average rate on a standard 30-year fixed was sitting at 7.58%, which had jumped up 0.19 points from the week before. That's the kind of movement that definitely catches people's attention in the housing market.

What caught my eye was the gap between the 30-year and 15-year options. If you went with a 15-year mortgage back then, you were looking at 6.69% - still high, but noticeably lower than the 30-year rate. The tradeoff was obvious though: your monthly payment would be way higher since you're crushing the loan in half the time. On a $100k mortgage, we're talking $881 a month versus $704 for the 30-year.

The APR numbers tell a different story than just the interest rate. When you factor in all the fees and charges, the 30-year APR was 7.55% (up from 7.30% the previous week), while the 15-year APR came in at 6.63%. That's why understanding the difference between interest rate and APR actually matters - the APR shows you the real total cost.

Jumbo mortgages were also moving up that week. The 30-year jumbo rate hit 7.27%, up 0.24 points. Over the past year, jumbo rates had ranged from a low of 5.63% to a high of 9.00%, so there was pretty wild volatility happening.

If you're trying to figure out what a mortgage would actually cost you, the math is straightforward but tedious. Take your home price, subtract your down payment, plug in the interest rate and loan term, and you can calculate your monthly payment. But honestly, just using a mortgage calculator is way easier - you throw in your numbers and it spits out what you'd pay monthly, plus the total interest over the life of the loan.

Looking back at those mortgage interest rates from July 2023 is a good reminder of how much rates can shift. People who locked in deals around that time were dealing with some serious rate environments.