Folds and binding, explained.
A flat sheet becomes a brochure with a fold and a book with a spine. Here is what each fold and each binding does, what it is good for, what it asks of the paper and the file, and how to count pages.
The six folds most brochures use.
Every brochure starts flat. The fold decides how it opens, how it reads and what envelope it fits.
Half fold
One fold down the middle, four panels. A letter sheet becomes a 5.5 x 8.5 in program or greeting card; an 11 x 17 in sheet becomes a four-page newsletter. The simplest fold, and the one that reads most like a book: open it and the inside is one spread.
Tri-fold (letter fold)
Two folds, six panels. One outer panel folds in first (the flap) and the other closes over it as the front cover, so the flap is 1/16 in narrower than the other two. Which side the narrow panel sits on depends on the face: on the inside spread it is the right-hand panel; on the outside it is the left-hand one, with the front cover on the right. The standard brochure, and the one that fits a number 10 envelope: 8.5 x 11 in folded to 3 11/16 x 8.5 in. A file with three equal panels bows at the edge and never closes flat.
Z-fold
Two folds in opposite directions, so the sheet zigzags instead of tucking. All three panels are the same width and any of them can be the front. It opens in one pull, which suits maps, step-by-step instructions and anything meant to be read as one wide sheet. Also the fold for a letter going into a window envelope.
Gate fold
Two flaps fold in to meet at the center, like doors. Open them and a full-width spread is waiting behind. Made for a reveal: a menu, an invitation, a product with one big photograph. The flaps stop about 1/4 in short of each other (1/8 in each side of center) so they never ride up on each other, and on cover stock both folds are creased on our finishing equipment before folding.
Double gate
A gate fold that is then folded in half down the middle, so it closes to a little over a quarter of the sheet. Eight panels and two reveals: first the doors, then the spread. The most theatrical fold a single sheet can do, and the one that most wants a heavier paper, creased on every fold, so it holds its shape.
Roll fold
Four or more panels that roll in on each other from one end, each panel 1/8 in narrower than the one that wraps it. It reads panel by panel, a step at a time, which suits a guided story or a set of instructions. On 8.5 x 14 in, four panels close to 3 11/16 x 8.5 in and fit a number 10 envelope.
Three more folds, and what every panel measures.
Accordion, French and cross fold, then the panel widths for every fold on this page, in inches.
Accordion
Every fold the opposite way to the last: a pleat. Four panels a side on a legal sheet, more on a longer one, all the same width, so it opens like a fan. Every panel is a full page, which suits a timeline, a series of photographs or a small catalog. On text weight it folds easily and mails flat in an envelope; on cover stock, creased on every fold, it stands up on a table like a little screen. Past four panels it springs open in the hand, so it wants a band, a box or an envelope.
French fold
Folded in half, then in half again the other way, and printed on one side only. Fold it with the printed side out and every surface you see is printed: the front, the back and the inside spread, with the blank side sealed inside the folds. The doubled paper gives the piece four layers, so a text-weight sheet feels like card. A quiet trick for a wedding invitation or a note card, and only one side is printed.
Cross fold
The same two folds at right angles, on a sheet printed both sides. Fold a letter sheet this way and you have eight pages at 4.25 x 5.5 in (printers call a folded sheet of pages a signature), with the top edge still folded until it is trimmed. Big presses build books this way, in 8- and 16-page signatures from one large sheet. Our booklets are the simpler case: each sheet folded once and nested.
| Fold | Closes to | Panels | Panel widths | Fits |
|---|---|---|---|---|
| Half | 5.5 x 8.5 in | 4 | 5 1/2 and 5 1/2 | A9 (5 3/4 x 8 3/4 in) or 6 x 9 in envelope |
| Tri-fold | 3 11/16 x 8.5 in | 6 | 3 11/16, 3 11/16 and 3 5/8 (the flap: right on the inside, left on the outside) | Number 10 envelope |
| Z-fold | 3 2/3 x 8.5 in | 6 | 3 2/3, three times | Number 10 envelope |
| Gate | 5 5/8 x 8.5 in | 6 | 2 11/16, 5 5/8 and 2 11/16 | 6 x 9 in envelope |
| Double gate | 2 13/16 x 8.5 in | 8 | 2 11/16, 5 5/8 and 2 11/16, then in half | Number 10 envelope |
| Roll, on 8.5 x 14 in | 3 11/16 x 8.5 in | 8 | 3 11/16, 3 9/16, 3 7/16 and 3 5/16 (rolls in) | Number 10 envelope |
| Accordion, on 8.5 x 14 in | 3.5 x 8.5 in | 8 | 3 1/2, four times | Number 10 envelope |
| French or cross | 4.25 x 5.5 in | 8 | Halves, both ways | A2 envelope, 4 3/8 x 5 3/4 in |
Set the panels to the widths in the table (equal only where it says so: the z-fold and the accordion), and export without fold lines drawn in; we mark the folds on the proof. Ask and we will send a template with the panels in place. Everything in the table mails at the letter rate in its envelope (up to 6 1/8 x 11 1/2 in and 1/4 in thick). A piece mailed bare is a self-mailer, and USPS wants it tabbed shut, on 70 lb text or heavier, with the final fold along the bottom; say it will mail bare and we set it up that way.
Score first on anything heavier than text.
A fold on cover stock without a score cracks and shows white along the crease. The score, a crease pressed in on our finishing equipment before the fold, is what stops it.
100 lb text
Text weight folds as it is
Up to about 100 lb text (148 gsm) the sheet folds clean without help, as long as the fold runs with the grain. This is why brochures are text weight: 80 lb text for a mailer, 100 lb text for something handed out. Fold against the grain and even text weight shows a rough, fuzzy edge.
65 lb cover
Cover weight needs a score
From about 65 lb cover (176 gsm) up, the fibers on the outside of the fold stretch too far and snap. A score is a channel pressed into the sheet first, so the paper folds along it and the outside face rounds instead of cracking. Every folded card, gate fold and booklet cover we make on cover stock is creased on our finishing equipment, and laid out with the grain along the fold wherever the sheet allows (two folds at right angles cannot both have it).
Solids
A solid across the fold
A dark solid across a fold is the hardest case: dry toner sits on the surface with less give than the paper, so it cracks first and shows white. We crease it, and we crease heavier text weights too when a solid crosses the fold, and it may still show a fine line. When it matters, keep heavy solids off the fold, choose a lighter paper, or add a soft touch or matte laminate over the whole sheet: this is the one job a film does that our usual UV coating cannot, holding the ink together at the crease and hiding most of it.
Scoring is a line on the quote, the same line as the folding. If a piece is cover weight and folds, assume it needs one; we will say so on the quote either way. Perforation, for a tear-off reply card, a ticket stub or a coupon, is done on the same finishing equipment and is its own line.
Count pages, not sheets.
One number causes more back and forth than any other. Here is how we count, so we count the same way.
x4
A sheet folded once is four pages
Each side of each leaf is a page. Fold a sheet in half and you have two leaves and four pages: a front, two inside, a back. A saddle-stitched booklet is these sheets nested one inside another, so the count is always a multiple of four: 8, 12, 16, 20 and so on up to 64.
1
The cover counts
Page 1 is the front cover, page 2 is the inside front cover, and the last page is the back cover. A 16-page booklet with a separate cover is 12 inside pages plus the 4 pages of the cover. If you have 14 pages of content, you have a 16-page booklet and two pages to fill; a blank inside back cover is normal and nobody notices it.
8 to 64
The online booklet
Our saddle-stitched booklet takes any count from 8 to 64 in steps of four, at 5.5 x 8.5 in or 8.5 x 11 in, with Natural or Silk inside, an Uncoated, Gloss or Self cover, and from 25 to 500 copies. Enter the page count with the cover included and the price updates as you go.
Sheets are our problem, not yours: a 16-page booklet at 5.5 x 8.5 in is four folded sheets nested together; a 64-page one is sixteen. You tell us pages; we work out the sheets.
Saddle stitch: folded, nested, stapled.
The everyday binding. Quick, and right for anything up to about 64 pages.
How it works
The folded sheets are nested one inside the next, opened over a saddle, and two wire staples go through the fold. Then the three open edges are trimmed so every page is the same size. The result opens nearly flat and lies down on a table, which a glued spine will not do. There is no spine to print on: the edge is a fold.
64
Page limits, by paper
The limit is thickness, not the count. On the papers the online booklet uses the stitch holds 64 pages well; on a heavier uncoated text plan on fewer (coated sheets are thinner and go further); cover weight only ever wraps the outside. Past the limit the booklet stays sprung open, the staples strain and creep grows. Fewer than 8 pages is not a booklet but a folded sheet, which is fine too.
Creep, and the wider safe area
Nested sheets push the inside pages outward at the open edge, and the trim cuts them back, so the inner pages come out a little narrower. On a 64-page booklet of 80 lb text it is close to 1/8 in. We shift the pages inward as we lay them out on the sheet so the margins stay even, but this is why booklets get a 0.25 in safe area instead of 0.125 in, and why a picture across the spine should forgive a small shift.
Cover: separate or self
A separate cover on 80 lb to 100 lb cover stock, creased on our finishing equipment and wrapped around the inside sheets, makes a booklet feel finished and protects the pages. A self cover uses the inside paper for the cover too: lighter, simpler, and right for a program used once or a handout. Beyond the covers the online booklet offers, a heavier cover, or a UV coating or a laminate over it, is a line on the quote.
Grain runs along the spine on every booklet we make, so the pages turn softly and the book closes. The online booklet is saddle stitched; anything with more pages, or with a spine, is quoted through Start a project.
Perfect binding: a square spine, glued.
The paperback. Pages stacked as single leaves, the spine roughened and glued, a cover wrapped around and the whole thing trimmed flush.
40
Minimum pages
Below about 40 pages of 80 lb text the spine is under 1/8 in and there is too little for the glue to hold or for anything to print on; a saddle stitch is the better book. From 40 to 64 pages either binding works and the choice is about the look. Above that, perfect binding is the answer up to about 1 1/4 in of spine, around 400 pages of 80 lb text, where case binding takes over.
3/8 in
Spine width, from the paper's thickness
Half the page count times the caliper of the inside paper (its thickness, in points), plus twice the caliper of the cover, which wraps both sides. 100 pages of our 100 lb smooth uncoated text at about 7 pt is 50 leaves x 0.007 in, 0.35 in, plus 0.02 in of cover: a 3/8 in spine. Coated papers are thinner per pound, so the same count makes a slimmer book. We measure a blank made up from the actual paper before you finish the cover.
The cover wraps, so the file needs a spine
The cover is one flat piece: back cover, spine, front cover, printed as a single spread with bleed on every side. We give you the spine width; you build a cover page as wide as the spine plus twice the finished width, at the finished height. Keep the spine type 1/8 in short of the spine's edges on each side, and think twice about type on a spine under 1/4 in, because the glue and the hinge land within a hair of where the file says, not exactly on it.
It does not lie flat
A glued spine opens to about 120 degrees and closes itself if you let go. Two things follow. Keep a 0.5 in inside margin (the gutter) on every page so text does not run into the curve. And never run a line of type across the spine; a picture across it works if nothing important sits in the middle 0.5 in. For a workbook meant to lie open, choose coil or wire instead.
Perfect binding is quoted through Start a project. It carries a setup, so it suits a run rather than a handful of copies, and it adds a day to a job: the glue cures overnight before the trim.
Coil and wire: lies flat, turns all the way around.
For anything used with both hands: manuals, workbooks, cookbooks, calendars, notebooks.
Spiral coil
A plastic coil wound through a row of small holes along the bound edge. It turns a full 360 degrees, lies flat, shrugs off being dropped, and comes in colors. Coils are sized to the book, from a few sheets up to about a 1 in coil, which holds around 3/4 in of paper: roughly 250 pages of 80 lb text plus covers. The pages shift a little against each other when open, which nobody minds in a cookbook.
Wire-o
Twin loops of wire through a row of rectangular holes, closed onto the pages. It also lies flat and turns all the way around, and the pages stay aligned when open, which suits a presentation, a calendar or anything with pictures across the spread. A wrap-around cover can hide the wire and give the book a printable spine. A little less tough in a bag than coil: a crushed wire stays crushed.
1/2 in
The punching margin
The holes take about 3/8 in at the bound edge, so keep type and anything that must not be punched 0.5 in from that edge on every page, both sides. A page that bleeds is fine; the holes go through the ink. Front covers are often clear plastic or a laminated card and back covers a heavier board, so the book stands up to use.
Case binding, quoted
The hardcover. Pages sewn or glued into a block, then glued into a rigid case of board wrapped in printed paper or cloth, with a spine to print or foil. For a book that should last for years or sit on a shelf: a history, a family cookbook, a company anniversary. We quote it through Start a project; it takes weeks rather than days, and it suits tens of copies and up, not a handful.
Coil and wire take single pages of any mix: a cover on card, tabs on heavier stock, an insert on a different paper. Tell us which pages are which in the notes and we build the order into the proof. Both are quoted through Start a project, as case binding is.
Which binding for what.
Where we start when someone asks. The page count usually decides; the rest is how the piece will be used.
| Binding | Pages it suits | Lies flat | Spine to print on | Typical use |
|---|---|---|---|---|
| Folded sheet | 4 to 8 | Yes | No | Brochures, programs for one evening, mailers |
| Saddle stitch | 8 to 64 | Nearly | No | Programs, catalogs, magazines, look books, newsletters |
| Perfect bound | 40 to about 400 | No | Yes | Books, reports, thick catalogs, anything for a shelf |
| Spiral coil | 20 to about 250 | Yes, and folds back | No | Manuals, workbooks, cookbooks, planners |
| Wire-o | 20 to about 250 | Yes, and folds back | With a wrap cover | Presentations, calendars, notebooks |
| Case bound | 40 and up | Nearly, if sewn | Yes | Hardcover books, keepsakes; quoted |
Saddle stitch when
The count is 64 pages or fewer, the piece will be read at a table or handed out, the run is small, and there is no need for a spine. Programs, catalogs and magazines, nearly always, from 25 copies up.
Perfect bound when
The count is over 64, or the piece will live on a shelf or a desk and needs a spine so it can be found, or it should feel like a book in the hand. From 40 to 64 pages both work: perfect binding for the look, saddle stitch to lie open. Below 40 it is not a choice; the spine is too thin.
Tabs, inserts and pockets
Index tabs are cut to shape on cover stock, on our cutting plotter or laser so there is no die to make, and bound in with the pages, mostly in coil and wire books and sometimes perfect bound. A reply card or a coupon can be perforated on our finishing equipment so it tears out clean. Inserts are anything loose: a reply card, a price list that changes, a business card in a slit on the inside cover, a pocket glued to the back cover. All of it is a line on the quote; tell us what goes where and we lay it out on the proof.
And how to set up the file, binding by binding. Every proof shows the folds, the spine and the punching, so nothing here is a surprise.
- Every binding: single pages in reading order, cover included, each page at the finished size with 0.25 in of bleed. No spreads (a perfect-bound cover is the one exception, below); we put the pages where they go on the sheet.
- Saddle stitch: a multiple of four pages, 8 to 64, and a 0.25 in safe area from the outside edges to allow for creep.
- Perfect bound: the inside pages as above with a 0.5 in gutter, plus the cover as one spread (back, spine, front) at the spine width we give you.
- Coil or wire: 0.5 in clear at the bound edge on every page, both sides, and a note on which pages are on which paper.
- Folded pieces: a two-page PDF at the flat size, outside then inside, panels at the widths in the table above, and no fold lines drawn in the art; we mark them on the proof.
- Tell us the fold or binding in the notes when you order or start a project, and which pages go on which paper if they differ.
Not sure which fold or binding? Say what it is for.
Tell us what the piece has to do (mail, sit open on a table, live on a shelf, survive a kitchen) and we will suggest the fold or the binding and a paper to go with it.