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Walk Score, Bike Score, Transit Score — what they actually measure
Walk Score, Bike Score, and Transit Score are widely-cited 0-100 indices that often appear on Zillow + Redfin listings. They're computed by Walk Score (a Redfin company) using public datasets. Here's what's under the hood and where they break down.
Published 2026-04-25 · Last reviewed 2026-04-26 · methodology
Walk Score's algorithm
Computes for any address: distance from a starting point to N nearby amenities (grocery, coffee, schools, parks, restaurants, etc.).
Each amenity weighted by category importance + intersection density + block length (small blocks = walkable).
Output: 0-100 scale. 90-100 = Walker's Paradise. 70-89 = Very Walkable. 50-69 = Somewhat Walkable. 25-49 = Car-Dependent. 0-24 = Car-Dependent.
Methodology paper: walkscore.com/methodology.shtml
Where it breaks
POIs from open data + commercial sources can lag reality 6-18 months. New restaurants under-counted; closed ones still in.
Algorithm doesn't see hills (San Francisco vs flat suburb) — same Walk Score, very different lived experience.
Doesn't account for sidewalk quality, lighting, crime, or weather. A 90 in Detroit ≠ 90 in Boston in February.
Suburban-with-trail areas often under-score because trails ≠ amenities.
Bike Score
Considers bike lanes, hills, road connectivity, destinations.
More variable than Walk Score; many cities only marginally biking-friendly even at high scores.
Pair with strava heatmaps + local cyclist forums for ground truth.
Transit Score
Distance to + frequency of transit lines (bus, light rail, heavy rail, ferry).
Frequency matters more than presence. A bus that runs once an hour at peak is functionally absent for most commuters.
City Transit Score averages: NYC 84, SF 80, Boston 74, Chicago 65, DC 71, Seattle 60, LA 53.
Better verification stack
1. **Walk Score** (walkscore.com) — baseline 0-100.
2. **Google Maps walking-time matrix** — set 5-7 important destinations + check actual walking time at the address.
3. **Local transit agency** — pull actual schedule + frequency of nearest stop.
4. **Strava heatmaps** — Strava global heatmap shows where cyclists actually ride.
5. **Visit at the time of day you'd use it** — Tuesday 6pm differs from Saturday 11am.
What zipradar shows
Walk/Bike/Transit are NOT in our 12-dimension federation. walkscore.com is the canonical source — linked from /methodology/.
Pair walkability with school district + crime + air quality for full quality-of-life pre-purchase audit.
Related zipradar topics
Glossary terms used here
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