Stealing this from Julie's blog because I like it a lot:
My Kirkland apt has a walk score of 89
How it works:
1. Type an address
2. See what's nearby
3. Get your Walk Score
What is Walk Score?
We help homebuyers, renters, and real estate agents find houses and apartments in great neighborhoods. Walk Score shows you a map of what's nearby and calculates a Walk Score for any property. Buying a house in a walkable neighborhood is good for your health and good for the environment.
How It Works
Walk Score helps people find walkable places to live. Walk Score calculates the walkability of an address by locating nearby stores, restaurants, schools, parks, etc.
What does my score mean?
Your Walk Score is a number between 0 and 100. The walkability of an address depends on how far you are comfortable walking—after all, everything is within walking distance if you have the time. Here are general guidelines for interpreting your score:
90 - 100 = Walkers' Paradise: Most errands can be accomplished on foot and many people get by without owning a car.
70 - 90 = Very Walkable: It's possible to get by without owning a car.
50 - 70 = Some Walkable Locations: Some stores and amenities are within walking distance, but many everyday trips still require a bike, public transportation, or car.
25 - 50 = Not Walkable: Only a few destinations are within easy walking range. For most errands, driving or public transportation is a must.
0 - 25 = Driving Only: Virtually no neighborhood destinations within walking range. You can walk from your house to your car!
How it Works
Walk Score™ uses a patent-pending system to calculate the walkability of an address based on:
The distance to walkable locations near an address.
Calculating a score for each of these locations.
Combining these scores into one easy to read Walk Score.
This website rates locations based on their proximity to established businesses. For example, the Friend's (TV Show) apartment has a walk score of 100, while Bill Gates's suburban Medina house has a low walk score of around 6.