Walk Score, the popular Web tool that allows home shoppers to ascertain the pedestrian-friendliness of prospective neighborhoods, now has a cousin.

Enter Transit Score, a similar online widget that allows users to calculate approximate commute times, transportation costs, and transit options for specific points on the map. Funded, in part, by the Rockefeller Foundation, the tool was created by Front Seat, the Seattle-based civic software incubator that created Walk Score.

Still a work in progress, Transit Score currently mines data from 40 major U.S. cities. Ratings from zero to 100 are assigned to specific neighborhoods, indicating how well an address is served by public transportation. A score between 90 and 100  indicates a “Rider’s Paradise” offering multiple transit options within a quarter mile. Areas on the lowest end of the spectrum might have a single bus route, at best.

The tool already has early adopters. Online brokerage Zip Realty was the first to integrate Transit Score ratings into the home listings on its website. The company has been advertising Walk Scores since 2008.

“The costs of driving to and from work and daily activities are only growing, and the time spent in traffic is lost forever,” Walk Score CEO Josh Herst said in a release. “[This new tool will] make it easy for consumers to quickly understand how much the location of their home and workplace impact their daily lives.”

Some might argue that location matters more than ever. Consumers waste 4.2 billion hours and 2.8 billion gallons of gas in traffic each year, according to estimates by the Texas Transportation Institute. And they’re starting to see commuting as a significant factor in quality of life, while government officials and planning review boards see it as an enemy of environmental protection.

It’s also a pocket book issue. Households in traditional suburbs can now spend as much as 32% of their income on transportation, whereas those in walkable areas with greater access to public transit may allocate as little as 12%, according to estimates by the Center for Neighborhood Technology, a think tank with offices in Chicago and San Francisco.

Research by the Natural Resources Defense Council has also linked pedestrian-friendly, transit-oriented neighborhoods with lower foreclosure rates.

Jenny Sullivan is a senior editor covering architecture, design, and community planning for BUILDER magazine.