This is the pump I travel with.
A Filzer Mini Pump. It’s compact, light, and even has a fold out handle and foot hold. It’s a great Pump.
The Pump also displays pressure in both PSI and BARS. The BARS display is in a larger font, and given my eye sight these days, is easier to read. So, I inflate in BARS.
I have been experimenting with tire pressure. The roads I ride are a mix of smooth Tarmac, older paved roads with numerous, mostly filled, potholes, and even some packed gravel. Today, I lowered the pressure to 3.5 BARS in front, and 5 in the rear. Or, 51 and 73 PSI respectively, as opposed to 73 and 102 PSI I have been riding.
Guess what. I did not notice any difference in speed, but the ride was noticeably more comfortable.
Who said you can’t teach an old dog new tricks?
PedalWORKS 
Lower pressures and wider tyres seem to be the new vogue. When I started road riding I had 700×23 tures at 110psi. Now I’m running 28mm at just under 80psi. More comfortable and just as fast/faster as they absorb the road. Also just gone tubeless and loving it.
They make a difference. I’m riding with Compass 32’s on this bike and 35’s on the all road. I haven’t sacrificed any speed, and not only are they more comfortable but handle better too, particularly on the descents.