# A4 Ring Binder Dimensions

The most common A4 ring binder dimensions are 50 mm, 40 mm, 30 mm, 25 mm, 20 mm and 15 mm capacities. However, there are other capacities and measurements available.

### Common Binder Capacities and Sizes

These binders have five measurements: A, B, C, D and E. A4 20 mm, 25 mm, 30 mm, 35 mm, 40 mm, 45 mm, 50 mm, 55 mm and 65 mm capacities all have the same measurements A (311 mm) and measurements E (4.5 mm).

A4 15 mm capacity measurement A is 311 mm, while measurement B is 535 mm. Measurement C is 250 mm; measurement D is 26 mm and measurement E is 4.5 mm.

A4 20 mm measurement B is 546 mm and measurement C is 252 mm. Its D measurement is 33 mm. A4 25 mm has a measurement B of 557 mm. its measurement C is 255 mm. Its D measurement is 38 mm.
A4 30 mm: measurement B, 572 mm; measurement C, 255 mm and measurement D 38 mm. A4 40 mm has a 592 mm B measurement, 265 mm C measurement and 53 mm D measurement.

A4 45 mm’s B, C and D measurements are 621 mm, 276 mm and 60 mm. A4 50 mm measurements are 637 mm B, 279 mm C and 70 mm D. A4 55 mm capacities have 648 mm measurement B, 282 mm C and 75 mm D. A4 65 mm capacity measurement A is 671 mm, 286 mm measurement B and 90 mm measurement D.

### How to Find the Right A4 Ring Binder Dimensions

Determine how much paper is going to be put in the binder. This can be done using the mm capacities stated above (40 mm, 30 mm, 20 mm etc). Next you have to choose between a D ring and a round ring. The round ring is fastened at the binder spine. These makes it easier to flip pages, but the rivets might end up on the spine or striking pockets.

The D ring is set at the rear cover. The book ends up looking like a block but they are also very easy to turn. Most binders use two rings. The centers measure 80 mm.

Because there are many A4 ring binder dimensions, you should have no problems finding the right one for your papers. You just need to choose among the available ring capacities: they are 15, 20, 25, 30, 40 and 50 mm.