It depends a lot upon the action, single/double shot guns are going to invariably kick the hardest, as all of the recoil energy is going into the grip/buttstock/etc, there’s no action to absorb some of the recoil and chamber the next round, bolt/lever actions kick a little less hard because there are places for the recoil gasses to escape, semiautos have a reasonably pleasant recoil, because they use some of the recoil energy to work the action and chamber the next round
revolvers have more percieved recoil than semiautos, for the same reasons as above
personally, the hardest recoiling long gun is a tie between my Mossberg 500 12-gauge firing a full 3" Magnum shotshell, or my 7.62x54R Mosin-Nagant M-44 Carbine, the Mossy has a small recoil pad as factory stock, the M-44 has a solid steel buttplate, and no recoil pad, so the percieved recoil is higher in the Mosin
of the handguns I’ve shot, the most powerful, nastiest recoil was that of a S&W .44 Magnum revolver with a 6" barrel, that puppy wanted to smash me in the face, and I was ready (or so I thought) for it
of the handguns I’ve owned (and sold) my Taurus .357 with a 4" barrel was pretty nasty with full-powered .357’s, it was a combination of an extremely snappy, whippy recoil, and a palpable shockwave/muzzle-blast, that gun was a real hoot and a half 
of my current handguns, my CZ-75B 9mm has a little snappier recoil and a sharp-ish muzzle blast, it’s not too bad though, very controllable, my Kimber Custom II 1911-A1, however, is an absolute pussycat, it has a loud, low BOOMING report, but no supersonic CRACK (.45 ACP rounds are just slightly subsonic) and a nice, pleasant straight push back recoil, no snap or wrist torque, double and triple-taps are very easy and it’s exceptionally quick to get back on target, I absolutely LOVE the .45 ACP round