While searching on Ancestry.com and FamilySearch, the FREE Historical U.S. Counties Auto-Checker extension for Chrome automatically checks that the county existed in the year you are searching, checks for valid places, warns of boundary changes, and links to historical county lines on Google Maps for the place and years you are searching.

Now, in addition, if you are a randymajors.com Research Hub contributor, the Auto-Checker will ALSO automatically check all U.S. location facts on person profile pages on all Ancestry.com family trees! And your MAP links will open into ad-free fullscreen map windows any time you click a MAP link!

The screenshot above highlights how the tree fact-checking works on any person profile page on any Ancestry.com family tree. A few key features:

Quick links to interactive historical county maps for the year of each fact

Warnings if the county listed in your fact did not exist for the year of the fact (plus quick links so you can see what counties did exist in that year)

For ambiguous place names, possible matches are listed including map links (e.g. if the same township name exists in multiple places in the state, and you didn't list the county)

Once you link to the map page, as a contributor, you'll be working with ad-free full-screen maps that you can further explore the dates and places around your area, including both historical and present-day county lines, township boundaries and more. Details of exactly when each county formed, what counties it formed out of, statutes and more are listed above the map.

Remember, U.S. county boundaries have changed over 17,600 times since America was settled in colonial times. Don’t sabotage your search for ancestors by not knowing the correct county for the historical years you are researching. Install for free today and never let an ancestor fall of the map again!

Summary

FREE version: While using any Search form on Ancestry.com or FamilySearch.org, the Auto-Checker automatically checks that the county existed in the year you are searching, checks for valid places, warns of boundary changes, and links to historical county lines on Google Maps for the place and years you are searching!

CONTRIBUTOR version: Everything the free version does PLUS checks all of the U.S. location facts on person profile pages on all Ancestry.com family trees. The check includes everything listed in the bullet points above. Plus you get access to ad-free fullscreen versions of all map and search tools on randymajors.com. NEW: You can pause tree fact-checking at any time with the "Pause Auto-Checker" button in the Chrome extension popup. Note: tree fact-checking is not available for FamilySearch family trees.





The Historical U.S. Counties Auto-Checker Chrome extension makes use of the award-winning randymajors.com Research Hub’s Historical U.S. Counties on Google Maps tool, underpinned with the complete dataset of the authoritative Newberry Atlas of Historical County Boundaries.