What Size Are A7 Cards? | The 5×7 Catch

If you searched for A7 cards expecting one answer, you’ve already hit the confusion: the term means two different sizes depending on who is selling. Knowing which standard a vendor uses is the difference between a perfect invitation and a card that arrives comically small.

ISO A7 vs. US A7: Two Very Different Sizes

This is a genuinely small piece of paper — roughly the size of an index card.

The “A” here is a US convention from the greeting-card industry, not a reference to the ISO paper series. A 5 × 7 card is far larger than an ISO A7 sheet.

The two are not interchangeable. A 5 × 7 card does not match ISO A7 dimensions exactly, and vice versa.

How the Two Sizes Compare

Here’s how the two standards stack up against each other.

Which One Do You Actually Need?

If you’re shopping for greeting cards, wedding invitations, photo cards, or holiday announcements, the US 5 × 7 A7 is almost certainly what you want. That is the standard in American stationery shops for folded cards and the envelopes that hold them.

If you’re buying paper for printing, labels, or crafting in a metric context, the ISO A7 sheet applies. A vendor selling “A7 cards” in the US might mean either, so always check the listed dimensions before ordering.

The same caution applies to envelopes. If you’re ready to compare actual card options, our roundup of the best A7 greeting cards this year shows what’s worth buying.

Before you print or purchase, consult this paper and card size guide to confirm exactly what a vendor means by “A7.” Verify the finished size, the envelope compatibility, and whether the listed dimension is the flat sheet or the folded card. That one check prevents the classic mistake of ordering an ISO A7 label sheet when you meant a 5 × 7 card — or the reverse.