Two computer programs that can measure stamp perforations
Perforation Gauge
Perforation
Apparently, This Is How Reperforated Stamps Are Made These Days - Stamp Community Forum
How to measure perforations — Mystic Stamp Discovery Center
A stamp template with a frame simple perforation and a blanking stamp. Vector illustration. Can be used for poster, banner, cover, postcard, design, labels, stickers Stock Vector | Adobe Stock
Perforation Gauge
Unitrade Perforation Gauge for sale at Mystic Stamp Company
Stamp Smarter - Printable Perforation Gauges
Stamp perforations and their types - The Stamp Echo
Robert A. Siegel Auction Galleries, Inc. Sale - 973 Page 30
Postage stamp frame. Empty border template for postcards and letters. Blank rectangle and square postage stamp with perforated edge. Vector illustration isolated on white background 9733168 Vector Art at Vecteezy
Perforation varieties can make the difference
Postage stamp with perforated border Stock Photo - Alamy
Printable Perforation Gauge - Printable Word Searches