How does this work?

Covidvaxcount works by constantly checking the following three sources:

  1. The CDC Covid Vaccine Tracker
  2. Johns Hopkins Centers for Civic Impact vaccine data
  3. Individual state's vaccine dashboards, for example: Texas, New York, and Maine
As these sources report new numbers, Covidvaxcount will always take the most recent data for each state, and use that to calculate the current total number of vaccinations. Whichever source is used for each state is linked directly next to that state's name in the table on the home page.

This means that is always the most up to date count of how many people have been vaccinated in the US.

What is the number? Is it total doses administered?

The number calculated is described on the home page as: "members of the U.S. population who have received at least one dose of a COVID-19 vaccine". This means that the number represents how many people in the US have received at least one dose of a COVID-19 vaccine.

Therefore the number is different from "total doses administered", because the same person can receive two doses. Such a case would only count as one, because the number calculated is "number of people who have received the vaccine".