The Social Connectedness Index: A Large-Scale Dataset of Social Ties Across Geographic Locations
Drew Johnston, Theresa Kuchler, Manas Kulkarni, Johannes Stroebel
Data in Brief, 2026Social Connectedness Index
The Social Connectedness Index (SCI) is a globally comparable measure of the relative probability that Facebook users in two locations are friends.
Mapping Tools
Explore connections live, make publication-ready maps, compare how local friendship networks are, or group regions into connected communities.
Interactive Explorer
Click any country or region on an interactive globe and watch it light up with where it's most connected — the fastest way to discover surprising links.
Start exploring →Map Maker
Build polished, publication-quality SCI maps with full control over geography, colors, breaks, and titles — then download as an image or video to share them.
Make a map →Local Network Share
Set a distance and color every place by the estimated share of its Facebook friendship network that lives nearby.
Compare local networks →Connected Communities
Pick a region or country and a number of clusters, then watch its places group by how tightly they're connected — revealing which truly belong together.
Find clusters →Data
Download the Social Connectedness Index data for research, mapping, and analysis.
If you use the data, use these papers for your citation:
Research
Selected papers using the Social Connectedness Index to study cities, public health, and trade.
Social Proximity to Capital: Implications for Investors and Firms
Theresa Kuchler, Yan Li, Lin Peng, Johannes Stroebel, Dexin Zhou
Review of Financial Studies, 2022The Geographic Spread of Covid-19 Correlates with the Structure of Social Networks as Measured by Facebook
Theresa Kuchler, Dominic Russel, Johannes Stroebel
Journal of Urban Economics: Insights, 2022International Trade and Social Connectedness
Michael Bailey, Abhinav Gupta, Sebastian Hillenbrand, Theresa Kuchler, Robert Richmond, Johannes Stroebel
Journal of International Economics, 2021The Determinants of Social Connectedness in Europe
Michael Bailey, Drew Johnston, Theresa Kuchler, Dominic Russel, Bogdan State, Johannes Stroebel
Social Informatics, 2020Social Connectedness in Urban Areas
Michael Bailey, Patrick Farrell, Theresa Kuchler, Johannes Stroebel
Journal of Urban Economics, 2020Social Connectedness: Measurement, Determinants, and Effects
Michael Bailey, Rachel Cao, Theresa Kuchler, Johannes Stroebel, Arlene Wong
Journal of Economic Perspectives, 2018Press
Selected coverage of the Social Connectedness Index and research using social connectedness data.
Social Media Contacts in Virus Hotspots Encouraged Self-Isolation
Facebook friendships can help predict Covid-19 spread, study finds
Facebook data could help predict the spread of future diseases
How public transportation predicts social media connections in New York City
In New York, Friendships Run Along Subway Lines
Mind the gap: New York City friendships form around the SUBWAY line you ride
What Determines Your Social Network? In New York, Your Subway Line.
How Connected Is Your Community to Everywhere Else in America?
Far-flung Facebook friends may be good for your health
What our Facebook network reveals about us
Facebook Friends From Far Away Are a Trait of Rich Communities