Booklet Creep & Safe Margin Calculator
Enter the page count, measured paper caliper, cover construction, and safe-margin target. The calculator shows the maximum creep, the remaining innermost margin, and the compensation for each text sheet.
Maximum booklet creep (mm)1.5
- Text sheets
- 16
- Innermost remaining outer margin (mm)
- 6.5
- Required prepress outer margin (mm)
- 6.5
- Margin check
- Pass; innermost pages keep the required outer margin.
- Maximum safe interior page count
- 124
Per-sheet creep and imposition schedule
| Text sheet from outside | Front page pair | Back page pair | Creep compensation (mm) |
|---|---|---|---|
| 1 | 64 / 1 | 2 / 63 | 0 |
| 2 | 62 / 3 | 4 / 61 | 0.1 |
| 3 | 60 / 5 | 6 / 59 | 0.2 |
| 4 | 58 / 7 | 8 / 57 | 0.3 |
| 5 | 56 / 9 | 10 / 55 | 0.4 |
| 6 | 54 / 11 | 12 / 53 | 0.5 |
| 7 | 52 / 13 | 14 / 51 | 0.6 |
| 8 | 50 / 15 | 16 / 49 | 0.7 |
| 9 | 48 / 17 | 18 / 47 | 0.8 |
| 10 | 46 / 19 | 20 / 45 | 0.9 |
| 11 | 44 / 21 | 22 / 43 | 1 |
| 12 | 42 / 23 | 24 / 41 | 1.1 |
| 13 | 40 / 25 | 26 / 39 | 1.2 |
| 14 | 38 / 27 | 28 / 37 | 1.3 |
| 15 | 36 / 29 | 30 / 35 | 1.4 |
| 16 | 34 / 31 | 32 / 33 | 1.5 |
Positive creep values are cumulative compensation amounts for each text sheet counted from the outside toward the center.
Confirm whether the imposition system expects total creep, per-sheet creep, or a half-shift applied to each page.
How to use this calculator
- Enter the interior page count, or the full self-cover page count, as a multiple of four.
- Choose millimeters or inches, then enter measured sheet caliper for the text stock.
- Choose whether the job uses a separate cover and enter its folded-sheet caliper when it does.
- Enter the artwork outer margin and the minimum safe margin required after trimming.
- Review the margin check, maximum safe page count, and per-sheet imposition schedule.
How booklet creep is calculated
Booklet creep, also called shingling, is the sideways movement of inner pages in a folded and saddle-stitched booklet. Each folded sheet wraps around the sheets inside it. As the stack gets thicker, the center sheets project farther toward the fore-edge before trimming, so important artwork near the outer edge can be cut too close unless the imposition compensates.
This calculator uses a cumulative-caliper model. Let P be the entered text page count, N = P / 4 be the number of folded text sheets, T be text-sheet caliper, Tc be separate-cover caliper, K be Tc for a separate cover and 0 for self-cover work, M be the artwork outer margin, and R be the required safe margin.
For sheet i, counted from outside to inside, the creep compensation is:
C_i = K + (i - 1)T
The maximum creep is on the innermost text sheet:
C_max = K + (N - 1)T
The innermost remaining margin is M - C_max. The prepress margin needed to preserve the required safe margin is R + C_max. To reverse the problem, the allowable creep is A = M - R. When A >= K, the largest safe text-sheet count is floor((A - K) / T) + 1, and the maximum safe interior page count is four times that sheet count. When A < K, even the separate cover consumes the available margin.
What moves the result most
The two strongest drivers are sheet count and measured caliper. A thin 16-page booklet may need little or no visible adjustment, while a thick coated 96-page saddle stitch can lose several millimeters at the center. A separate cover also matters because the first text sheet sits inside that cover, so its caliper is added before the text sheets accumulate their own creep.
Use measured caliper from the actual stock when possible. GSM and basis weight are not reliable thickness measurements because density, coating, finish, and compression vary by mill and grade. If the job mixes several text stocks, this one-caliper model is only an approximation.
What the schedule means
The table lists text sheets from outside to inside. The front and back page pairs use the normal saddle-stitch imposition order for the entered page count. The creep value is the cumulative compensation for that sheet; confirm with your software or bindery whether it wants that total value, an incremental value, or half of the total applied to each facing page.
What this leaves out
Actual creep can differ from caliper math because folding and stitching compress paper. Coatings, scoring, grain direction, fold geometry, trim sequence, and equipment-specific compensation are not modeled. For thick, coated, or high-page-count booklets, make a folded production dummy or ask the bindery for measured creep before releasing final files.
Worked example
For a 64-page self-cover booklet on text stock measuring 0.10 mm per sheet, there are 16 folded text sheets. The outer sheet has 0.00 mm of accumulated text creep, and the innermost sheet has (16 - 1) × 0.10 = 1.50 mm of maximum creep.
If the artwork outer margin is 8.00 mm and the required safe margin is 5.00 mm, the innermost remaining margin is 8.00 - 1.50 = 6.50 mm, so the margin check passes. The required prepress outer margin is 5.00 + 1.50 = 6.50 mm. The available creep is 3.00 mm, which allows floor(3.00 / 0.10) + 1 = 31 sheets, or 124 interior pages, before the margin target is exceeded.
Common questions
What is creep or shingling in booklet printing?
Creep is the way inner pages move outward in a folded booklet because every inner sheet wraps around the paper outside it. After trimming, those center pages can lose more outer margin than the outside pages. Shingling compensation moves pages or page content so the trimmed booklet keeps a consistent safe area.
How do I measure paper caliper?
Measure the thickness of a known stack of the actual stock, then divide by the number of sheets. For example, if 100 sheets measure 10 mm, the sheet caliper is 0.10 mm. A stack measurement is usually more reliable than trying to measure one sheet directly.
Why cannot GSM be converted directly to paper thickness?
GSM measures mass per square meter, not thickness. Two papers with the same GSM can have different calipers because coatings, fiber, finish, density, and compression differ. Use a published caliper from the mill or a physical measurement from the paper being printed.
Should creep compensation move content or the whole page?
That depends on the imposition workflow. Some systems shift page content inward, some alter page position, and some ask for total creep or half-shifts per side. Confirm the convention before entering a value, because the same number can be applied differently by different software.
Does a separate cover increase booklet creep?
Yes. A separate folded cover sits outside the first text sheet, so the text block starts with the cover caliper already outside it. This calculator adds the cover caliper to every text-sheet creep value when separate cover mode is selected.
When should I make and measure a folded dummy?
Make a folded dummy when the booklet is thick, uses coated stock, mixes stocks, has tight margins, or is near the saddle-stitch capacity of the bindery. A dummy captures compression and folding behavior that a simple caliper model cannot predict. It is also the best way to confirm the compensation expected by the shop.