About
FloodZoneCheck
FloodZoneCheck is a free research tool that gives you instant flood zone lookup for any U.S. address and ongoing monitoring to alert you when FEMA revises the flood map for a tracked property. The data comes directly from FEMA's National Flood Hazard Layer (NFHL), served through the same ArcGIS REST API that certified flood determination providers use — this is the authoritative source for flood zone designations nationwide.
The tool was built because free flood zone lookup tools exist, but none of them track map changes. FEMA periodically restudies floodplains as new data, development, and climate patterns emerge. A property previously mapped as Zone X (minimal risk) can be reclassified to Zone AE (high-risk) — suddenly triggering mandatory flood insurance for any federally-backed mortgage. FloodZoneCheck monitors these revisions so property owners and prospective buyers find out early, not at the closing table.
Every flood zone result on this site includes the zone designation, SFHA status, base flood elevation (when available), and a direct link to the official FEMA Map Service Center panel. The lookup works without an account — search any address freely. Create a free account to track up to three properties and receive change alerts. Upgrade to Pro for unlimited tracking.
Important Disclaimer
FloodZoneCheck is a free research tool using public FEMA data, not an official Standard Flood Hazard Determination. Lenders require a certified determination from a licensed provider. Zone boundaries can cross a single parcel — confirm exact risk and insurance requirements with FEMA or your insurer before relying on this for a purchase or insurance decision.
Data Source
All flood zone data is sourced from the FEMA National Flood Hazard Layer, accessed via the ArcGIS REST API at hazards.fema.gov/gis/nfhl/rest/services/public/NFHL. Geocoding uses the U.S. Census Bureau's free Geocoder API. Address coordinates are rounded to three decimal places for cache lookup. Zone data is cached for 30 days per coordinate pair since flood maps do not change frequently.
Questions or feedback? Contact us.