Buying a home is one of the biggest purchases a person will make in their lifetime. But how can you tell if you're ready for that type of commitment? To start, make sure you can afford the home.

To guide potential buyers, HSH.com, an online resource for mortgage and consumer loan information, has updated its list of how much salary a person needs to earn in order to afford a house in the top 27 metro areas.

The good news is that affordability improved in 22 markets, while mortgage rates fell in every metro area except San Diego, compared with the fourth quarter, HSH.com said.

That said, home prices did rise -- albeit slightly for the most part-- in 25 of the 27 metro areas compared with the first quarter of 2015.

The bad news is that for some areas, it still requires a significant amount of income to be able to afford a median-priced home.

HSH.com used first-quarter data for median home prices from the National Association of Realtors as well as its own data on first-quarter average interest rates for 30-year fixed-rate mortgages to determine how much salary it would take to afford the base cost of owning a home in 27 metro areas. The site defines "base cost" as the principal, interest, taxes and insurance. It doesn't include other added expenses such as maintenance, utilities, food, commuting costs and home renovations. 

HSH.com then used "standard 28 percent 'front-end' debt ratios and a 20 percent down payment subtracted from the NAR's median-home-price data to arrive at our figures," it said.

Here's how much you need to make to afford a home in the top 20 markets on HSH.com's list.