Ring gauge measures a cigar’s diameter in 64ths of an inch. Case openings are usually listed in millimeters. Enter either value below to convert between them, then compare the result with the opening or channel diameter in a product’s specifications.
How the conversion works
A ring gauge of 64 equals one inch, so diameter in inches is ring gauge ÷ 64, and diameter in millimeters is ring gauge × 25.4 ÷ 64. A 50 ring gauge cigar is 50 ÷ 64 = 0.78 in, or 19.8 mm. Going the other way, a 22 mm opening equals 22 × 64 ÷ 25.4 ≈ 55 ring gauge.
Common ring gauges
| Ring gauge | Diameter | Typical vitolas |
|---|---|---|
| 38 | 15.1 mm / 0.59 in | Lancero, panetela |
| 42 | 16.7 mm / 0.66 in | Corona, petit corona |
| 46 | 18.3 mm / 0.72 in | Corona gorda, lonsdale |
| 50 | 19.8 mm / 0.78 in | Robusto, toro |
| 52 | 20.6 mm / 0.81 in | Belicoso, torpedo, many toros |
| 54 | 21.4 mm / 0.84 in | Larger robustos and toros |
| 56 | 22.2 mm / 0.88 in | Gran toro |
| 60 | 23.8 mm / 0.94 in | Gordo |
| 64 | 25.4 mm / 1.00 in | Extra-large gordo |
Using the result
Compare the converted diameter with the case’s stated opening, channel width, or “maximum diameter”. A case whose opening equals the cigar’s diameter is a forced fit, not a comfortable one: lining, foot caps, and the maker’s hand measurement all use up clearance. Choose an opening at least 1 mm larger than the converted cigar diameter, and 2 mm if the cigar has a pressed or box-pressed shape, which is wider across the flat side than its nominal ring gauge suggests.
Diameter alone does not confirm fit. A cigar can be narrow enough and still too long for the case, so always check length against the stated usable or exterior length as well. The case fit checker does both comparisons in one step.
Figured cigars
Torpedos, belicosos, and other figurados are described by their widest ring gauge. The tapered head does not reduce the opening needed, because the body still has to pass through the channel. Perfectos with a bulged middle should be measured at the bulge.