I just think of kPa as a 'percentage' of atmosphere. 100% is atmosphere, 150% is 1.5 bar and 200% is 2 bar.
Also, 14.7 psi above atmosphere is easy to remember for us tuners, since that's also stoich. So 2 bar (200 kPa) is 14.7 and 150 is half that, etc.
This is all rough, since this actually changes with altitude, etc. But good enough for my brain to work things out without any math.