API for US ZIP, ZIP+4, and Canadian postal code data. One unified endpoint set covers North America — no separate APIs by country or data type.

What it does

• Address validation and standardization — production-grade parser with ZIP+4 append, refreshed monthly
• Radius search — centroid haversine and true spatial polygon intersection. Returns ZIPs/FSAs within range, with per-result pct_inside overlap percentage for spatial queries
• Unified lookup endpoint — accepts US ZIP, ZIP+4, Canadian FSA, full Canadian postal codes, or latitude/longitude inputs
• Autocomplete/typeahead — cities, counties, metros, states, FSAs, ZIPs
• Point-to-point distance — between any two postal points
• Census ACS demographics — 2011–2024, 542 fields per ZIP across income, education, housing, social, and economic profiles
• Boundary lookups — Census tracts, congressional districts, state legislative areas, school districts — with computed intersection percentages per ZIP

What makes it different

• Licensed commercial data — not commodity or scraped sources
• Canadian postal coverage — most peers in this space are US-only
• True spatial radius — not just centroid haversine
• 14 years of historical ACS depth via API — unusual outside of raw Census downloads
• One endpoint for all of North America — no country-detection or input-routing logic to maintain on the client side

Pricing

• Free — 2,500 lookups/day, no credit card required, no expiry
• Developer — $49/mo, 100K credits, 300/min
• Professional — $149/mo, 350K credits, 300/min
• Business — $499/mo, 1.5M credits, 600/min
• Credit packs — one-time, from 25K ($19) up to 2M ($799)

Resources

• Docs
• OpenAPI spec
• Postman collection

USZipLookup.com is a fast, free zip code lookup tool built specifically for users who need quick, reliable answers about US postal codes - whether finding the zip code for a specific address, checking which areas a zip code covers, or validating address information before shipping or mailing. The platform is optimized for speed and simplicity, prioritizing quick, accurate results over cluttered interfaces.

Primary users include online sellers and small e-commerce businesses that need to validate customer addresses before shipping, logistics and fulfillment teams calculating delivery zones, individuals moving to a new area who need to confirm their new zip code, and developers or businesses researching US postal code structure for integration into their own systems. The tool's straightforward, no-friction design makes it especially useful for quick, on-the-fly checks rather than deep data analysis.

USZipLookup.com complements deeper lookup and reference functionality with content addressing common user questions — such as the difference between zip codes and postal codes, how zip+4 extensions work, and practical guidance on why accurate address validation matters for shipping cost accuracy and delivery reliability. This content is designed to capture both direct tool usage and broader informational search intent from users researching postal code topics.

Built with a focus on speed, mobile responsiveness, and straightforward usability, usziplookup.com is positioned as a lightweight alternative to bulkier, ad-heavy zip code tools. The platform is under continuous development, with plans to expand its address validation capabilities and deepen its content library to serve both casual lookups and more specific business use cases around shipping, logistics, and location verification.