Ring and disc binding sizes explained

If you are punching your own inserts, the pattern matters more than the paper size, because a page cut to the right size with the wrong holes is unusable.

Disc-bound is the standardised one

Unusually for this world, disc-bound is genuinely interchangeable. The mushroom-hole pitch is 25.40 mm, exactly one inch, across Levenger Circa, Staples ARC, TUL, Atoma and the Happy Planner. A page punched for one fits all of them.

Page size	Holes	Hole span	Gap at each end
Mini, 117 x 178 mm	7	152.40 mm	12.80 mm
Half Letter, 139.7 x 215.9 mm	8	177.80 mm	19.05 mm
Classic, 177.8 x 234.95 mm	9	203.20 mm	15.88 mm
Letter, 215.9 x 279.4 mm	11	254.00 mm	12.70 mm

Every one of those end gaps lands on an exact fraction of an inch: three quarters, five eighths, a half. That is a good sign the pattern is genuinely regular rather than something approximated from a photograph.

Disc sizes themselves run from about 19 to 25 mm for a portable notebook and 38 to 51 mm for something desk-bound. The discs do not affect the punch.

Six-ring is fragmented

Ring binders are the opposite: several patterns that look similar and are not compatible.

Pattern	Within group	Between groups	Total span
A5, six ring	19.05 mm	69.85 mm	146.05 mm
Personal, six ring	19.05 mm	50.80 mm	127.00 mm
Pocket, six ring	19.05 mm, evenly spaced	n/a	95.25 mm
Mini, five ring	19.05 mm, evenly spaced	n/a	76.20 mm

The 19.05 mm within-group spacing is constant, which is why the patterns look alike at a glance. The gap between the groups is what differs, and it is what makes A5 and Personal inserts non-interchangeable.

Franklin Covey and Day-Timer use a different system again: seven rings on a 140 x 216 mm page, 25.40 mm between individual rings and 38.10 mm between groups. It is not compatible with six-ring A5 despite the page sizes being close.

For reference, A4 four-hole punching is ISO 838: 80 mm spacing, tolerance plus or minus 0.5 mm.

How much margin a punch needs

More than the hole diameter, because the punch removes material and the ring then occupies the space.

• Six-ring Pocket and Personal: 12.70 mm
• Six-ring A5 and Half Letter: 15.00 mm
• Disc-bound Mini and Half Letter: 12.70 mm
• Disc-bound Classic and Letter: 19.05 mm
• Spiral or comb, for comparison: 18 to 20 mm
• Wire-O or coil: 25.4 mm

Disc punches need relatively more than their hole size suggests, because they remove a mushroom shape rather than a circle.

Mirror the margin across a spread

This is the mistake that is invisible until the pages are in the binder.

On a facing spread the punched edge alternates: the left page is punched on its left, the right page on its right. A file that puts the binding margin on the same side of every page puts your writing under the rings on every second sheet.

Our files handle this automatically when you choose a binding, and it is worth checking on anything you download elsewhere. Print two pages, hold them side by side, and see whether the wide margins are on the outside or both on the left.

Punches

A dedicated punch for your system is the only thing that produces consistently square holes. They are not cheap and they last decades.

If you are punching occasionally, the alternative is a punched page used as a template with a single hole punch. It is slow and the result is visibly hand-made, but it works.

What does not work is a standard two- or four-hole office punch on a small page. The spacings do not match anything.

Paper weight for inserts

100 to 120 gsm for anything that will be turned daily for a year. 80 gsm works and will soften at the holes within a few months.

Reinforcement stickers on the punched edge extend the life of 80 gsm considerably and are cheap.

One thing worth knowing: branded organiser paper from some of the large planner names is only 60 to 80 gsm and can curl in a laser printer. Plain 100 gsm copier paper is often the better choice for home printing.