Coin Holder & Album Size Finder
Enter a coin's diameter to find the nearest standard flip, capsule, or album-slot size — measured in millimetres, matched to the industry's standard size ladder.
Nearest standard holder size
Nearest common capsule/flip/album size — coin diameters vary slightly by mint and era, so test-fit one before buying in bulk.
One measurement, several holder styles
Once you know a coin’s standard size in millimetres, that same number applies whether you’re buying cardboard 2x2 flips, rigid direct-fit capsules, or an album with circular Mylar slots — manufacturers largely converge on the same size ladder.
Because coin diameters can drift by a fraction of a millimetre between mints and eras, buy one holder first and confirm the fit before ordering in bulk for an entire set or type.
Frequently Asked Questions
Why is a '2x2 flip' always 2 inches, no matter the coin?
The '2x2' name refers to the outer cardboard, which is a standardized 2-inch square regardless of the coin inside. What changes between sizes is the inner circular window stamped into that same 2x2 card — that's the millimetre size this tool finds.
How should I measure a coin's diameter?
Use digital calipers across the widest point of the coin's face, not the edge thickness. Measure in millimetres for the most precise match against standard holder sizes.
Why doesn't the tool return an exact match to my measurement?
Coin diameters vary slightly by mint, era, and even individual strike, and manufacturers only produce holders in a defined ladder of standard sizes. This tool finds the closest standard size — always test-fit one holder before buying a full box.
Should I use a cardboard flip or a rigid capsule?
Flips are inexpensive and fine for sorting or short-term storage, but their sticky tape and softer material aren't ideal for higher-grade or valuable-to-you coins. A rigid, direct-fit capsule offers better physical protection for a coin you want to keep long-term.
Sizing estimate only — always test-fit a holder before buying supplies in bulk.