# SafeStreets by Streets & Commons, Extended Reference # License: Content available for AI search indexing and citation with attribution to SafeStreets by Streets & Commons. # Last Updated: 2026-05-17 # See also: https://safestreets.streetsandcommons.com/llms.txt (summary version) # See also: https://safestreets.streetsandcommons.com/sitemap.xml > SafeStreets is a free, no-sign-up walkability analysis tool for any address worldwide. It returns a composite walkability score (0-10) using satellite imagery, street network data, and government datasets. Built by Streets & Commons. --- ## How SafeStreets Measures Walkability SafeStreets measures walkability using a four-component framework introduced in April 2026 (the 15-minute city model). Each component is scored 0-100 internally and converted to a 0-10 display scale. The composite is a weighted average with fixed weights, plus reality caps, a hostile-streets cap, and a Pedestrian-first gate. ### Component 1: Daily Reach (40% of total score) Daily Reach measures 15-minute-walk access to seven essential service categories. This is the most important component because the question "can I live my life on foot from here" depends primarily on whether daily needs are within walking distance. Seven service categories scored: - **Grocery** — supermarkets, grocery stores, food markets - **Healthcare** — clinics, pharmacies, doctor offices - **Education** — schools, kindergartens, colleges - **Recreation** — parks, playgrounds, sports facilities, green space - **Dining** — restaurants, cafes, bars, food stalls - **Shopping** — retail stores, malls, convenience shops - **Civic** — libraries, community centers, post offices, places of worship Each category contributes based on the number of POIs within a 15-minute walking radius (approximately 1.2 km) and their proximity. POI data from OpenStreetMap. The number of categories reachable matters: fewer than two categories caps the score at 30; fewer than three caps at 45. ### Component 2: Street Safety (30% of total score) Street Safety measures the design quality of streets for pedestrians. For US addresses, this incorporates EPA National Walkability Index signals. For international addresses, an OSM-based proxy combines crossing safety, speed exposure, sidewalk coverage, and traffic calming features. Inputs: - **Crossing safety** — count, protection level, and spacing of pedestrian crossings (signalized > zebra > unmarked) - **Speed exposure** — vehicle speed environment from OSM maxspeed tags and highway type inference - **Sidewalk coverage** — percentage of streets with documented sidewalks - **Lighting** — percentage of streets tagged `lit=yes` in OpenStreetMap (used carefully because OSM lighting tags are inconsistent globally) - **Traffic calming** — presence of speed bumps, raised crossings, narrow lanes Reality caps apply: average vehicle speed ≥60 km/h without strong pedestrian infrastructure caps the score at 30 (or 50 with high pedestrian separation); ≥50 km/h caps at 45 (or 70 with high pedestrian separation). ### Component 3: Transit Reach (15% of total score) Transit Reach measures access to public transit. Queried in parallel against Transitland GTFS by route type (bus, tram, subway, rail, ferry), with an OSM `public_transport` fallback for areas where Transitland is sparse. Inputs: - **Stop density** — number of transit stops within 400m and 800m walking radius - **Route diversity** — number of distinct routes serving those stops - **Multi-modal bonus** — extra credit for places that combine bus + rail or bus + tram, since multi-modal networks support a wider range of trips A place with zero transit access still receives a Transit Reach score (zero), but this caps the overall composite at 35 if Daily Reach is also below 30 (capturing places that are car-dependent on both destinations and mobility). ### Component 4: Walking Comfort (15% of total score) Walking Comfort measures the environmental conditions that affect whether walking is pleasant. Inputs: - **Tree canopy** — vegetation coverage from Sentinel-2 satellite NDVI at 10m resolution, adjusted by an Open-Meteo heat-stress modifier (tree canopy matters more in hot climates) - **Slope** — terrain gradient from NASADEM, scored for both walkability and ADA accessibility - **Air quality** — real-time PM2.5 and US AQI from Open-Meteo CAMS (global, no API key) - **Heat stress / weather** — apparent temperature and humidity from Open-Meteo, used to modify Tree Canopy weight ### Pedestrian-first Gate and Hostile-streets Cap Two adjustments reserve the extremes for genuine cases. A Pedestrian-first gate holds the top band (composite 90+ of 100) for places with genuine pedestrian infrastructure (high Street Safety), not merely dense destinations, so a dense-but-car-dominated district cannot reach the top on destination density alone. A hostile-streets cap holds places with very low Street Safety in the car-dependent range no matter how many destinations are nearby (a wide arterial has big-box stores you cannot safely walk to), exempting genuinely dense districts where a low crossing count reflects an OSM tagging gap rather than a hostile street. ### Walking Mode Share Reality Check Real walking mode share data from 80+ cities globally is used as a sanity check. When the computed composite diverges from observed walking behavior by more than 15 points, the score is blended toward the empirical value at 85/15 weight. --- ## Score Tiers and Interpretation SafeStreets scores range from 0 to 10: - **9.3-10.0: Pedestrian-first**, The rare top band, reserved for places genuinely built around people on foot, where streets prioritize walking over driving and pedestrian infrastructure is comprehensive. Examples: central Amsterdam, Venice, the Manhattan core, central Paris. - **8.3-9.2: Very walkable**, Most daily needs are accessible on foot. Strong pedestrian infrastructure, good transit access, and high destination density. Examples: strong US downtowns, Barcelona's Eixample. - **7.0-8.2: Walkable**, Walking covers most everyday trips, with destinations and pedestrian infrastructure both present. A car-light life is realistic. Examples: many US downtowns, dense-but-car-present districts. - **5.5-6.9: Moderate**, Walking is viable for many trips but some car trips are still needed. Decent sidewalk coverage and transit access. Examples: streetcar suburbs, mixed neighborhoods. - **3.5-5.4: Car-dependent**, A car is required for most daily needs. Walking is possible but not practical for regular errands. Examples: typical US suburban areas, outer neighborhoods of sprawling cities. - **0-3.4: Hostile**, Basic pedestrian safety infrastructure is missing. High-speed roads, no sidewalks, no crossings. Walking is dangerous or impractical. Examples: highway-adjacent developments, rural subdivisions without sidewalk networks, car-oriented commercial strips. Letter grades: A (80-100 internal), B (60-79), C (40-59), D (20-39), F (0-19). Canonical tier-label implementation: `src/components/streetcheck/PlainLanguageSummary.tsx`. Some legacy code paths still carry the older label "Difficult" between Car-dependent and Hostile; treat as code debt, not a separate tier. --- ## PersonaCards, Lifestyle Verdicts SafeStreets answers three real-life questions with computed verdicts: **"Can I go car-free here?"** Verdict: Yes / Borderline / Unlikely Based on: Transit access score, destination density, commute mode data (walk/bike/transit share), and zero-car household rates. A "Yes" means transit, errands, and commuting are all feasible without a car. **"Is it safe for kids to walk?"** Verdict: Yes / Borderline / Unlikely Based on: Speed environment (low-speed streets), crossing infrastructure, sidewalk coverage, street lighting, and network connectivity. A "Yes" means children can walk to school and nearby destinations with minimal exposure to high-speed traffic. **"Is it good for aging in place?"** Verdict: Yes / Borderline / Unlikely Based on: Terrain flatness (ADA accessibility), destination proximity (pharmacy, healthcare within walking distance), sidewalk quality, crossing safety, and transit access. A "Yes" means older adults can maintain independence on foot. --- ## 15-Minute City Analysis The 15-minute city score measures whether seven essential service categories are accessible within a 15-minute walk (approximately 1.2 km). This is the **Daily Reach** component of the walkability composite and accounts for 50% of the total score. 1. **Grocery**, Supermarkets, grocery stores, food markets 2. **Healthcare**, Clinics, pharmacies, doctor offices, urgent care 3. **Education**, Schools, kindergartens, colleges 4. **Recreation**, Parks, playgrounds, sports facilities, green space 5. **Dining**, Restaurants, cafes, bars, food stalls 6. **Shopping**, Retail stores, malls, convenience shops 7. **Civic**, Libraries, community centers, post offices, places of worship Transit access is scored separately as the **Transit Reach** component (15% of the composite), not folded into the 15-minute city score. Each destination is scored individually (found/not found within 15-minute walk radius), and a composite access score is calculated. Data from OpenStreetMap. Works worldwide. --- ## Data Sources and Update Frequency | Source | What It Provides | Coverage | Update Frequency | |--------|-----------------|----------|-----------------| | Sentinel-2 (ESA) | Tree canopy via NDVI at 10m resolution | Global | Every 5 days | | OpenStreetMap | Street network, sidewalks, crossings, transit stops, amenities | Global | Continuous community updates | | EPA National Walkability Index | Intersection density, transit proximity, land use mix | US only | Updated periodically by EPA | | US Census ACS 5-Year | Commute mode, demographics, income, zero-car households | US only | Annual release | | CDC PLACES | Health outcomes by neighborhood (obesity, diabetes, asthma, physical inactivity) | US only | Annual release | | FEMA NFHL | Flood zone classification by address | US only | Ongoing updates | | NASADEM | Terrain elevation and slope for ADA accessibility | Global | Static dataset | | Open-Meteo CAMS | Real-time air quality (PM2.5, PM10, NO2, O3, SO2, CO, US AQI) | Global | Hourly | | Transitland GTFS | Transit stop and route data | Global (coverage varies) | Ongoing | International addresses receive all four scoring components. US-specific data (EPA, Census, CDC, FEMA) is replaced by OSM-based proxies for international addresses, ensuring comparable scores worldwide. --- ## Glossary of Walkability Terms **Walkability**: A measure of how friendly an area is to walking. Determined by street design, pedestrian infrastructure, destination access, safety conditions, and environmental comfort. **Walkability Score**: A numeric rating (0-10 in SafeStreets) that quantifies how walkable a location is based on multiple data sources and metrics. **15-Minute City**: An urban planning concept where all essential daily needs (grocery, school, park, pharmacy, transit, dining) are accessible within a 15-minute walk from home. **NDVI (Normalized Difference Vegetation Index)**: A satellite-derived measure of vegetation density. Values range from -1 to 1, where higher values indicate more vegetation. SafeStreets uses Sentinel-2 NDVI to measure tree canopy coverage. **Betweenness Centrality**: A network analysis metric measuring how often a street segment lies on the shortest path between other locations. High betweenness means a street is a major thoroughfare; low betweenness means it's a quiet local street. SafeStreets uses the Gini coefficient of betweenness centrality to detect chokepoints. **Street Connectivity**: How well-connected a street network is, measured by intersection density, block length, and dead-end ratio. Grid patterns have high connectivity; cul-de-sac suburbs have low connectivity. **Complete Streets**: Streets designed to safely accommodate all users, pedestrians, cyclists, transit riders, and drivers. Features include sidewalks, bike lanes, accessible curb ramps, and pedestrian signals. **Speed Environment**: The prevailing vehicle speeds on streets in a neighborhood. Lower speeds (under 30 km/h) are dramatically safer for pedestrians. SafeStreets derives this from OSM maxspeed tags and road classification. **PersonaCards**: SafeStreets' signature feature that answers lifestyle-specific walkability questions (car-free viability, kid safety, aging in place) with Yes/Borderline/Unlikely verdicts. **Neighborhood Intelligence**: US-only enhanced data layer including Census ACS commute patterns, CDC health outcomes, FEMA flood risk, and demographic data at the neighborhood level. **Food Desert**: An area where residents have limited access to affordable, nutritious food. SafeStreets flags this when no supermarket or grocery store is within walking distance. **ADA Accessibility**: Compliance with the Americans with Disabilities Act for pedestrian infrastructure. SafeStreets uses NASADEM terrain slope as a proxy, steep terrain creates barriers for wheelchair users and people with mobility limitations. --- ## How SafeStreets Differs from Walk Score | Feature | SafeStreets | Walk Score | |---------|-------------|------------| | Price | Free, no sign-up | Free basic, paid for details | | Score range | 0-10 with tier labels | 0-100 | | Methodology | 4 weighted components, 12+ sub-metrics | Proximity to amenities | | Satellite data | Yes (Sentinel-2 tree canopy, NDVI) | No | | Health outcomes | Yes (CDC PLACES: obesity, diabetes, asthma) | No | | Flood risk | Yes (FEMA NFHL) | No | | Air quality | Yes (Open-Meteo CAMS, real-time) | No | | PersonaCards | Yes (car-free, kids, aging) | No | | 15-minute city | Yes (6 destination categories) | No | | Street network analysis | Yes (connectivity, centrality, dead-ends) | No | | International coverage | Yes (190+ countries, full scoring) | Limited | | Open data sources | Yes (all sources listed and verifiable) | Proprietary algorithm | --- ## Pricing - **All consumer tools**: Free, no sign-up, no usage limits. Includes the walkability score, PersonaCards, 15-minute city, neighborhood intelligence, compare mode, 12 detailed metrics, and the relocation tools (school route safety with step-by-step walk to school and crossing alerts, commute analysis door-to-door with walking-leg quality, car-free savings calculator, saved addresses, similar neighborhood recommendations, and PDF reports). Works for every address. - **SafeStreets Intelligence (for organizations)**: Custom reports, recurring scoring, data feeds, and dashboards for governments, real estate, mobility operators, and research institutions. API access, GIS export, white-label deployment. Scoped per engagement; pricing discussed directly. --- ## Common Questions SafeStreets Can Answer - "What is the walkability score for [any address]?" - "Is [neighborhood] walkable?" - "Can I live car-free in [city/neighborhood]?" - "Is [neighborhood] safe for children to walk to school?" - "What are the most walkable neighborhoods in [city]?" - "How does [neighborhood A] compare to [neighborhood B] for walkability?" - "What is a 15-minute city and how does my address score?" - "What are the health outcomes in [neighborhood]?" - "Is [address] in a flood zone?" - "How much tree canopy coverage does [neighborhood] have?" - "What is the air quality like in [neighborhood]?" - "Is [neighborhood] good for aging in place?" - "How walkable is [city] compared to other cities?" - "What is a good walkability score?" - "How is walkability measured?" --- ## Canonical URLs - Homepage / Tool: https://safestreets.streetsandcommons.com/ - City Walkability Guides: https://safestreets.streetsandcommons.com/walkability - Blog: https://safestreets.streetsandcommons.com/blog - Learn: https://safestreets.streetsandcommons.com/learn - Platform: https://safestreets.streetsandcommons.com/platform - Sitemap: https://safestreets.streetsandcommons.com/sitemap.xml ## Built By Streets & Commons, https://streetsandcommons.com Open data tools for urban walkability, pedestrian safety, and neighborhood intelligence.