Black Lives Matter

Black Lives Matter is a movement against police violence and racial inequality in the United States. Pew Research Center traces the phrase to a Facebook post by the activist Alicia Garza in July 2013, written after George Zimmerman was acquitted in the killing of Trayvon Martin. It spread as a hashtag from there.

Scale, measured where it can be measured

The movement has no membership roll, and protest crowd sizes are contested. Hashtag volume is one of the few quantities that has been counted consistently over its whole history, and Pew has tracked it since 2013.

Across the decade to June 2023, Pew collected more than 44 million tweets carrying #BlackLivesMatter. Roughly 24.5 million of them — more than half of the ten-year total — were posted in the summer of 2020, after George Floyd was killed by a Minneapolis police officer. Within that summer, Pew counted 47.8 million uses between May 26 and June 7, 2020, peaking at nearly 8.8 million on May 28 alone.

The 44 million and 47.8 million figures come from different collections with different windows and methods and should not be compared with each other; each is reported here against its own source.

What the counts do not measure

Hashtag volume records posting on one platform. It is not a count of participants, protests or supporters, and Pew does not present it as one. Pew also notes that 55% of the tweets carried other hashtags alongside #BlackLivesMatter, which is a reminder that the tag circulated inside wider conversations rather than marking a discrete membership.

An earlier version of this page asserted a four-phase institutional history and a list of digital “impacts” — none sourced, and the institutionalization claim in particular conflates the decentralized movement with the separate national organizations that adopted its name. That distinction matters and is not made here, because no source cited on this page establishes it.