How many labels fit on a roll?
Capacity depends on the usable annular area between the core and finished roll OD, the effective material caliper and the repeat pitch. Labels across the web multiply the number of finished labels produced by each machine-direction repeat.
Web length = π × (OD² − Core OD²) ÷ (4 × thickness)
Labels = floor(web length ÷ pitch) × labels across
Labels = floor(web length ÷ pitch) × labels across
Use effective caliper for better estimates
Nominal face-stock thickness alone is not enough. The release liner and adhesive contribute to wound thickness. If you have a known roll with a verified label count, you can calibrate an effective caliper from that roll and use the same stock value for future estimates.
Capacity is not the same as a guaranteed production count
Converters may add leader, trailer, splices, setup waste or specified winding limits. Use this result as geometric capacity, then apply your own production rules when setting a sellable roll quantity.