When it comes to finding the right card size, you really can’t go wrong. You can even choose cards as large as letter paper if you really want them to stand out. However, if you’re looking for something more traditional, perhaps you should stick to the A6 card size.
The size of an A6 card is 105 × 148.5 millimeters or roughly 4.1 × 5.8 inches. It is precisely equal to a quarter of the size of a sheet of A4 paper (210 × 297 millimeters or 8.1 × 11.7 inches).
Why Choose A6 Cards?
There really is no objective reason why anyone would choose A6 (105 × 148 millimeters) over A5 (148 × 210 millimeters) or A7 (74 × 105 millimeters) paper.
That said, if you’re looking for a more traditional card size, you should probably choose a card that is sized A6 or A7. The typical greeting card or birthday card won’t be too far off from the A6 size.
Most of these cards measure 4.25 × 5.5 inches (108 × 140 millimeters), so sheets of A6 cardstock won’t stick out like a sore thumb.
Understanding ISO 216 Standards
ISO 216 is the international standard for paper sizes. It uses the A, B, and C series to determine how large the piece of paper is. This standard is a foreign concept in North America and Latin America, which are used to using letter-size and legal-size sheets of paper.
In the A-series, there are eight sizes, starting from A0 and ending at A7. The higher the number following the series letter, the smaller it is in size.
To understand how large one size is in comparison to another, all you really have to remember is that the dimensions of the subsequent number in the series will equal half the size of the previous number. For instance, an A1 sheet of paper (594 × 841 millimeters) is equal to half the size of a sheet of A0 paper (841 × 1189 millimeters).
The following table should give you a clearer picture of how each number in the series relates to the others in terms of size.
|Sheet Size||Dimensions (L × W in mm)||A0||A1||A2||A3||A4||A5||A6||A7||A8|
|A0||841 × 1189||–||2×||4×||8×||16×||32×||64×||128×||256×|
|A1||841 × 594||1/2×||–||2×||4×||6×||8×||16×||32×||64×|
|A2||420 × 594||1/4×||1/2×||–||2×||4×||6×||8×||16×||32×|
|A3||420 × 297||1/8×||1/4×||1/2×||–||2×||4×||6×||8×||16×|
|A4||210 × 297||1/16×||1/8×||1/4×||1/2×||–||2×||4×||8×||16×|
|A5||210 × 148||1/32×||1/16×||1/8×||1/4×||1/2×||–||2×||4×||8×|
|A6||105 × 148||1/64×||1/32×||1/16×||1/8×||1/4×||1/2×||–||2×||4×|
|A7||105 × 74||1/128×||1/64×||1/32×||1/16×||1/8×||1/4×||1/2×||–||2×|
|A8||52 × 74||1/256×||1/128×||1/64×||1/32×||1/16×||1/8×||1/4×||1/2×||–|
Using this table, you can immediately tell how large one size is in relation to the next within the same series.