For comparison:

Mark 1 – "Little Boy" gun-type uranium weapon (used against Hiroshima). (13–18 kilotons, 1945–1950)
Mark 3 – "Fat Man" plutonium implosion weapon (used against Nagasaki), effectively the same at the "Gadget" device used in the Trinity (nuclear test) with minor design differences. (21 kilotons, 1945–1950)

So more than Hiroshima and Nagasaki combined.

But it can be "dialed back" to only 5 or 10 kilotons.