Card Sleeve Sizes Explained: Standard, Japanese and Oversized

Sleeve names are marketing. Sleeve measurements are not. Buy on measurements and you will never order the wrong size again.

The two sizes that cover most cards

Standard size — about 66 x 91 mm sleeves for a 63 x 88 mm card. This covers Pokémon, Magic: The Gathering, Lorcana, One Piece and most western trading card games.

Japanese size (also called small or yu-gi-oh size) — about 62 x 89 mm sleeves for a 59 x 86 mm card. Yu-Gi-Oh! and many Japanese-language sets use it. A Japanese-size card in a standard sleeve has several millimetres of slack, and that slack lets dust in and lets the card slide.

Oversized cards — jumbo promos, some box toppers — need sleeves sold specifically for them; there is no standard.

Penny sleeves vs deck sleeves

A penny sleeve is a thin, soft, clear sleeve for storage. It is not built for shuffling and will split if you play with it.

A deck sleeve is thicker, often with an opaque back and a textured or matte face, and is built to be shuffled hundreds of times.

Storage collections use penny sleeves. Play decks use deck sleeves. Valuable cards use both.

Double sleeving, properly

Double sleeving means the card goes into a snug perfect-fit inner sleeve, then that goes into a deck sleeve. Load the inner sleeve so its opening faces the closed end of the outer sleeve — that way no edge of the card is exposed on any side.

It is worth doing for expensive cards in a played deck. For a bulk collection sitting in a box, it is overkill.

Thickness and the "microns" number

Sleeve thickness is usually quoted in microns. Around 40 to 60 microns is a normal deck sleeve; thicker sleeves are more durable and harder to shuffle. There is no single correct number — thicker for protection, thinner for feel.

Common mistakes

• Buying by brand name rather than checking the stated dimensions.
• Using standard sleeves on Japanese-size cards because the pack was cheaper.
• Assuming a sleeve protects against bending. It does not — that is a top loader's job.
• Reusing old sleeves that have gone cloudy. Hazing is abrasion, and it transfers.

After sleeving

A sleeved card still needs support. Store the collection upright in a box, keep anything valuable in a rigid holder, and read our guide to protecting trading cards for the full stack.

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