NFI Research has a list of the Top Public Libraries on Twitter
“These are the top public libraries on Twitter who 1) regularly update their page and communicate with their followers 2) use Twitter to advance/promote communication with their community 3) have a proportionate number of followers to following and 4) are currently active on Twitter. This list is updated regularly so if any public libraries would like to be added, please send information to list@nfiresearch.com”
As of today there are 179 libraries listed here and have a respectable number of followers:
17,000+ Followers
1 New York Public Library, New York, NY
4,000+ Followers
2 Houston Public Library, Houston, TX
2,000+ Followers
3 Kansas City Public Library, Kansas City, MO
4 Columbus Metropolitan Library, Columbus, OH
5 Hennepin City Library, Minneapolis, MN
6 Cincinnati Library, Cincinnati, OH
1,500+ Followers
7 Austin Public Library, Austin, TX
8 Grand Rapids Public Library, Grand Rapids, MI
9 Boerne Library, Boerne, TX
10 Mark & Emily Turner Memorial Library, Presque Isle, ME
11 Birmingham Public Library, Birmingham, AL
12 Cleveland Public Library, Cleveland, OH
13 District of Colombia Public Library, Washington, DC
14 Free Library of Philadelphia, Philadelphia, PA
15 Nashville Public Library, Nashville, TN
16 Queens Library, Queens, NY
17 Newberry Library, Chicago, IL
There are live links on the whole list.
Stephen

Ocean County Library will soon enter those ranks! @oceancountylib
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We’re the highest ranking Australian library on the list and not doing too bad at #131
High Country Library Corporation servicing North East Victoria