It is about 15% bigger in girth (just more or less 1 cm) than regular condoms.
Magnum condom size. Technically speaking, magnum condoms are wider or have bigger girth than regular condoms. This gets you your condom nominal width in millimeters (mm). Based on the text, a trojan magnum condom should fit snugly between men’s 8.07 inches and 9.5 inches in length, 2.13 inches and 2.36 inches in width, and between 8.07 inches.
Condoms should be tighter at the base so they don’t slip off, and whether you like a roomier condom or a tighter condom along the shaft and head is up to you. Girthwise, 5.3” or so should be plenty to wear a magnum snugly. Magnums are available in several varieties like original, ribbed.
By comparison, trojan’s standard enz condom measures 7.62 inches long and 2. At 6” girth, i find magnum xls to be pretty damn tight (they seem designed more for ~5.6” girth). 6 rows trojan™ and magnum™ condom size charts.
Getting the most from your condom starts with finding.