About Seattle Atlas
Seattle Atlas is an interactive map for exploring land use, transit, and urban planning in Seattle. View zoning rules, transit routes, bike infrastructure, and proposed development policies—all in one place.
What's on the Map
Three toggles control what you see: Zoning, Transit, and Bike Infrastructure.
Zoning
- Simplified view showing what can be built (homes & small shops, midsize residential, large buildings, downtown & highrise, etc.)
- Detailed technical zoning codes (NR, LR2, NC3, etc.), reflecting the Jan 21, 2026 adoption of One Seattle Plan Ordinance 127376
- Public parks, greenbelts, and open space—488 parks covering 12.1% of Seattle's land area
- Major institution campuses (universities, hospitals) labeled on inspected parcels
Transit
- Bus and ferry routes (King County Metro)
- Link Light Rail and Sounder commuter rail (Sound Transit)
- Bus stops and transit stations
Bike Infrastructure
- Protected lanes, neighborhood greenways, multi-use trails, shared lanes, and sharrows
How the Simplified View Works
Seattle's zoning code defines 30 distinct zone designations under Ordinance 127376 (Jan 21, 2026). The Simplified view groups these into six everyday categories so you can see at a glance what's allowed in each neighborhood. The Technical view keeps each official code separate. Both draw from the same underlying data — only the coloring differs.
- Homes & Small Shops — 69.4% of SeattleLow-density residential: houses, townhomes, multiplexes up to 6 units (9 with bonuses), ADUs, and corner stores and cafes newly allowed under the 2026 code. Includes NR (Neighborhood Residential), LR1 and LR2(Lowrise 1 & 2).
- Midsize Residential & Shops — 5.6% of SeattleApartment buildings roughly 3–8 stories, with ground-floor shops allowed in centers and on residential-commercial streets. Includes LR3 (Lowrise 3) and MR (Midrise).
- Large Buildings — 8.8% of SeattleCommercial corridors and urban villages where apartments sit above storefronts. Includes NC1, NC2, NC3 (Neighborhood Commercial), C1, C2 (Commercial), SM (Seattle Mixed, below 240 ft), and MPC (Master Planned Community).
- Downtown & Highrise — 2.3% of SeattleHigh-rise zones downtown, in the International District, and Pike Market — plus tower zoning outside downtown: First Hill, and the Seattle Mixed areas zoned for 240 ft+ towers around the U District, South Lake Union, and Northgate light rail stations. Includes HR (Highrise), SM (Seattle Mixed, 240 ft+), DMC, DMR, DOC1, DOC2, DRC, DH1, DH2 (Downtown zones), PSM (Pioneer Square Mixed), IDM, IDR (International District), and PMM (Pike Market Mixed).
- Institutions — 2.2% of SeattleHospitals and university campuses with their own development standards. Includes MIO (Major Institution Overlay).
- Industrial — 11.8% of SeattleManufacturing, maritime, and industrial land — mostly in SoDo, Ballard, Interbay, and Georgetown. Includes IC (Industrial Commercial), IB (Industrial Buffer), MML (Maritime Manufacturing/Logistics), II (Industry & Innovation), and UI (Urban Industrial) — the latter three created by the 2023 Industrial & Maritime Strategy.
Percentages reflect each category's share of Seattle's zoned land area. Parks and open space (an additional 12.1%) render as a separate layer.
Data Sources
All data is sourced from official government agencies and public datasets. Each zone's detail view links directly to its governing code section.
Zoning & Land Use
- City of Seattle Open Data Portal — zoning boundaries and classifications
- Seattle Municipal Code, Title 23 — zone classifications and development standards
- SDCI Land Use Code — official code descriptions and enforcement
- SDCI Map Books Legend (PDF) — zone code reference for official maps
Property & Parcels
- King County GIS — parcel boundaries, lot size, property use
- King County Assessor — assessed values, sales history
- Seattle Open Data — Building Permits — nearby permits and project costs
- Walk Score API — powers the Car-Free Scores section's walk, transit, and bike scores
Transit
- King County Metro (GTFS) — bus and ferry routes, stop locations
- Sound Transit (GTFS) — Link Light Rail, Sounder commuter rail
Bike Infrastructure
- Seattle Department of Transportation (SDOT) — protected lanes, greenways, multi-use trails, sharrows
Parks & Open Space
- Seattle Parks & Recreation — park boundaries, names, types, and acquisition history
Planning & Policy
- One Seattle Plan / Comprehensive Plan 2044 — citywide growth and land use policies
- Station Area Planning — proposed rezones around light rail stations
- ADU Code Updates — accessory dwelling unit policy changes
- Industrial & Maritime Strategy — industrial zone updates and protections
- Ballard Link Extension — planned light rail expansion (Sound Transit)
Open Source
Seattle Atlas is open source. View the code on GitHub.
The app is built with Next.js (App Router), React, and TypeScript, styled with Tailwind CSS, with icons from Tabler Icons. Maps are rendered client-side with Mapbox GL JS, with shareable map state (position, active layers, filters) synced to URL query params via nuqs. API routes validate input with Zod.
Source data is processed into vector tiles using Tippecanoe and hosted on Mapbox. The project uses Bun as its package manager and test runner, and is deployed on Vercel.
Seattle Atlas is not affiliated with the City of Seattle, King County, or any government agency. Data may not reflect the most recent changes—verify with official sources for legal determinations.