Method and sources
What we count, from which Census files, and what that leaves out.
The source
The Census Bureau publishes a Feature Names file for every county and county equivalent as part of TIGER/Line. We downloaded 3,234 of the 3,235 county files; the file for St. John, U.S. Virgin Islands was answered by the Census server with a "Request Rejected" page and is left out, from the Census Feature Names folder, on October 14, and the sha256 of each file is recorded in a per-file list in our repository.
2025 TIGER/Line Shapefiles Technical Documentation
File Name: tl_YYYY_<state-county FIPS>_featnames.dbf
The Feature Names relationship files contain a record for each feature name-edge combination and include the feature name attributes.
Multiple Feature Names relationship file records can link to the same edge.
What we count as a street
Method note A street, on this site, is one LINEARID that carries a primary name (PAFLAG P) on at least one edge classed S1200 or S1400 and has a non-blank base NAME. We count each LINEARID once nationwide. We group the Census NAME field exactly as stored. A street whose NAME is Main counts under Main whatever its separately recorded suffix or direction (Main St, N Main St, Main Ave). If NAME itself is N Main or S Main, it counts under that name, not under Main.
The LINEARID attribute identifies the linear feature to which the feature name applies.
The Census Bureau designates one of these names as primary and the others as alternates; usually the common street name (Oak Street) will be primary.
PAFLAG 1 String Primary/alternate flag
NAME 100 String Base name portion of the standardized name
Secondary roads are main arteries, usually in the U.S. highway, state highway, or county highway system.
Generally, a paved non-arterial street, road, or byway that usually has a single lane of traffic in each direction.
What that means for the numbers
The Census splits a named road into separate linear features at county lines, at gaps and wherever its spelling, class or primary/alternate status changes, so one long road can count as several streets here, and two streets with the same name in one town can count as one if the Census joined them. We exclude records with a blank NAME, alternate-name records (PAFLAG A) and every MTFCC class other than S1200 and S1400; the exclusion follows the Census classification, not our own check of a road's ownership or use.
The MAF/TIGER System breaks/ends linear elemental features when the feature name changes. All spelling differences result in a new feature. Features will also break at county boundaries, changes in primary/alternate designation, MTFCC, and gaps in the geometry.
Our count: 8,261,451 streets, 979,817 distinct base names, 3,231 counties with at least one street counted.
The name lookup
The lookup on the home page covers the 67,189 base names that appear on ten or more streets. Its CSV is names.csv.