Number of unemployment insurance claims is sometimes cited as an economic indicator, but it's definitely not the main measure of unemployment.
The BLS tracks six measures of unemployment rate via survey called U1-U6. U3 is the official unemployment rate, but they report the others as well[1].
For U3, you are considered unemployed if you do not have a job, have actively looked for work in the prior 4 weeks, and are currently available for work. U4 is that plus anyone who wants a job, but gave up looking because they don't think they will find one. U6 adds in people who only have part-time work but want full-time work.
The BLS tracks six measures of unemployment rate via survey called U1-U6. U3 is the official unemployment rate, but they report the others as well[1].
For U3, you are considered unemployed if you do not have a job, have actively looked for work in the prior 4 weeks, and are currently available for work. U4 is that plus anyone who wants a job, but gave up looking because they don't think they will find one. U6 adds in people who only have part-time work but want full-time work.
[1] https://en.wikipedia.org/wiki/Unemployment#United_States_Bur...
[2] https://www.bls.gov/cps/cps_htgm.htm#unemployed