How to read 0.02 caliper

To read a 0.02 mm vernier caliper, first note the main scale reading where the vernier scale's zero mark aligns, then identify which vernier scale line coincides exactly with any main scale line. The main scale reading gives you the whole millimeters and any visible 0.5 mm increment, while the coinciding vernier line number multiplied by 0.02 mm provides the fractional component. Add these two values together for the complete measurement.

For example, if the vernier zero is past the 34.5 mm mark on the main scale, and the 7th line on the vernier scale aligns with a main scale line, your reading is 34.5 mm + (7 × 0.02 mm) = 34.64 mm. The key skill is identifying which vernier line forms the straightest, most perfect alignment with a main scale graduation—this becomes easier with practice and good lighting. Always close the caliper jaws gently on the object without forcing, as excessive pressure can deflect the jaws and introduce measurement error. For consistent results, take multiple readings and verify they're within 0.02-0.04 mm of each other, as operator technique affects precision at this measurement level.