A4, A5, and A6 are the standard sizes used in most other countries and are measured in metric. . A5 in inches is 5.8x8.3 and is closest to US 5x7. A4 is 8.3 11. 7 and A6 is 4.1x5.8. I don't know how many it will actually hold but you would need additional A5 pockets as it only comes with 3. Hope this helps.