Fold types with diagrams and panel widths
The most common folds are the half fold (once down the middle), the roll fold and the Z fold (twice, giving six panels), and the gate fold, whose two flaps close towards the centre. On a roll fold, the inside panel has to be 2 to 3 mm narrower.
Contents of this page
Half fold
The sheet is folded once down the middle. An A4 sheet becomes a four-page A5 folder, an A3 sheet a four-page A4 folder. Both halves are the same width. This is the basis of every booklet: several half-folded sheets nested inside each other and stapled make a saddle-stitched booklet.
Roll fold
With a roll fold, the panels are folded inwards one after another, like a roll. A4 landscape becomes a six-panel DL leaflet. To stop the inside panel buckling, it has to be 2 to 3 mm narrower than the others. Usual widths for A4: 100, 100 and 97 mm. In the US, this fold is often called a letter fold or tri-fold.
On a roll fold, the narrow panel ends up on the inside. When you build the file, it goes on the right of the inside spread and on the left of the outside spread. Most printers offer templates for this, so nothing can go wrong.
Z fold and accordion fold
The panels are folded alternately forwards and backwards, like an accordion. Because no panel sits inside another, all are the same width: on A4 landscape, three panels of 99 mm. With three folds you get an eight-page accordion fold, and longer sheets give correspondingly more.
Gate fold and double gate fold
With a gate fold, the two outer quarters fold in towards the middle, like a pair of gates. Together the flaps are as wide as the centre panel, and each should be 1 to 2 mm narrower so they do not touch in the middle. If the whole piece is then folded once more down the centre, it becomes a double gate fold, sometimes called a closed gate fold.
Cross fold
For a cross fold, also called a French fold or right-angle fold, the sheet is first folded in half and then folded again at right angles to the first fold. An A4 sheet becomes A6, an A3 sheet becomes A5. Three cross folds turn a large press sheet into a 16-page section. A cross fold is also how a letter is folded to fit a C6 envelope.
All folds at a glance
| Fold | Folds | Pages | Panel widths on A4 landscape |
|---|---|---|---|
| Half fold | 1 | 4 | 148.5 + 148.5 mm |
| Roll fold | 2 | 6 | 100 + 100 + 97 mm |
| Z fold | 2 | 6 | 99 + 99 + 99 mm |
| Accordion fold | 3 | 8 | 4 × 74.25 mm |
| Gate fold | 2 | 6 | 74 + 149 + 74 mm |
| Double gate fold | 3 | 8 | 72 + 76.5 + 76.5 + 72 mm |
| Cross fold | 2 | 8 | A4 becomes A6 |
These are typical guide values. Printers specify slightly different measurements depending on their folding machines, so it pays to check their template.
Folding without cracking: creasing and grain
From about 170 g/m², the ink layer tends to crack along the fold, especially on dark areas. Printers therefore crease heavier paper first (in the US this is usually called scoring). A crease presses a groove into the paper so it folds cleanly. Grain direction matters too. Paper folds smoothly parallel to the grain and can split across it. More on paper types and grain direction.
Frequently asked questions
What is the difference between a roll fold and a Z fold?
On a roll fold, the panels fold inwards and the inside panel must be narrower. On a Z fold, the panels fold back and forth and are all the same width.
How wide are the panels of a roll fold on A4?
Usually 100, 100 and 97 mm. The 97 mm panel goes on the inside.
From what paper weight do I need creasing?
As a rule of thumb from about 170 g/m², and with dark solid areas even below that.
Which fold turns A4 into DL?
A roll fold or a Z fold. Both divide a landscape A4 sheet into three panels.