You rang?

Gauge accuracy is expressed relative to the scale. A gauge rated with a 1% accuracy means it's 1% of the overall scale, not the reading. So 1% on a 0-160psi gauge means it's accurate to ±1.6psi, and a 0-30psi gauge is accurate to ±0.3psi.

This rated accuracy usually applies to the enter of the scale, with fall off to both ends. Also gauges repeatedly used to the top end of their range, will suffer some wear and tear, and lose calibration over time (a slow process).

So, the right gauge for tires at 100psi or so is 0-160, though a 0-120 will be OK also. (center scale of the wider scale is probably as more accurate than end scale of the smaller range). Those riding tires at 40-60psi would do better with a gauge that tops out at about 100 or so.

A decent rule of thumb is to select a gauge with a range roughly 1.5-2 times the target pressure.