Bottom 5 (pre Trump)?

Nixon, Andrew Johnson, Fillmore, Taylor, Jackson

I think all the pre-Lincoln presidents who punted or excused slavery enabled the war of southern insurrection, and Johnson went out of his way to prevent a proper accounting by the South for their insurrection.

We’re still living with the repercussions of that to this day.

Trump jumps to the worst of the worst, as his scandals and criminality take every single crisis/scandal by every prior admin - combines it into one huge scandal of epic proportions, and dumbs it even further.

Dubya is up there, but behind those 5.

Top 5? That’s a harder question, but think
Washington, Lincoln, FDR are easy top 3, and you can argue each merits top spot. Washington gets the nod because he set the bar so high and was setting precedent with every action. Truman and Eisenhower are up there as well.