Methodology
SurnameRoot publishes free reference pages about U.S. surnames: frequency, rough ethnic distribution, and origin/meaning notes. This page explains where the numbers come from, how we classify origin, and what this site is not.
1. Primary data: U.S. Census surname files
Demographic tables on surname pages use the U.S. Census Bureau surname frequency products for 2000 and 2010 (publicly published files of names occurring at least 100 times). Fields we surface include:
- National rank and count of people with that surname
- Proportion per 100,000 people
- Self-reported race/ethnicity distribution associated with the name in the Census product
When we compare 2000 vs 2010 ranks, we use those two releases only — we do not invent intermediate years.
2. Origin and meaning notes
Origin labels (e.g. English, Irish, Spanish, German) and short meaning blurbs are produced from a combination of:
- Linguistic patterns (common prefixes/suffixes and orthography)
- Etymological reference patterns and editorial rules in our classifier
- Alignment checks against Census ethnicity distributions (a weak signal, never proof of your ancestry)
Many surnames have multiple legitimate origins, spelling variants, or were adopted through migration and translation. When evidence is thin, pages should read as provisional, not as a court record.
3. State “most common surnames” hubs
State pages estimate which surnames are likely common in a state by combining national surname frequencies with state demographic composition (BISG-style weighting). They are estimates for exploration, not official state registries.
4. Quality tiers (index policy)
As of 2026-07-25, we concentrate indexable surname leaves on a merit set (approximately the top 2000 U.S. Census-ranked names present on the site, plus pages that already earn organic search visits). Other surname leaves may remain available to readers and internal links but are marked noindex,follow so crawlers focus on stronger URLs. Hubs (home, top-100, states, letters, methodology) stay indexable.
5. Heritage Report (paid)
The optional Heritage Report is a separate product: a longer written keepsake PDF for a chosen surname. It is not required to use the free encyclopedia. Refunds are available via the delivery email if you are not satisfied — see the report checkout flow.
6. Corrections
If you spot a factual error in Census transcription or a harmful misclassification, contact us via the site contact path and we will review. Material corrections are reflected on this methodology date line when policies change.