In offset printing, paper is the biggest cost factor — up to 70% of total costs go to paper. Failing to optimise sheet imposition is literally throwing money away. The sheet imposition calculator shows how many units (individual formats) fit on a press sheet and compares portrait and landscape orientations to find the maximum yield.
Step by Step: How to Use the Imposition Calculator
- Select the sheet size: B1 (700 × 1,000 mm), B2 (500 × 700 mm), A0 (841 × 1,189 mm), or a custom sheet size. B1 is the standard press sheet in web offset printing.
- Enter the unit format: Finished format (e.g. A5 = 148 × 210 mm) plus 3 mm bleed on all sides = 154 × 216 mm cut format. Never forget the bleed — otherwise white borders appear in the final product.
- Allow for the gripper margin: The gripper margin (10–15 mm) on one edge of the sheet is needed for press transport and is not available for imposition units.
- Check both orientations: The calculator shows the unit in portrait and landscape — sometimes a 90° rotation yields significantly more units per sheet.
- Use the result: Number of units × print run = minimum number of press sheets. For print cost calculation: sheet price × number of sheets + make-ready costs.
Practical Examples
Example 1 – A5 flyer on B1 sheet: B1 (700 × 1,000 mm), gripper margin 15 mm → usable sheet 700 × 985 mm. Portrait units (154 × 216): 4 × 4 = 16 units. Landscape units (216 × 154): 3 × 6 = 18 units → landscape orientation saves 2 sheets per 16-unit layer, i.e. 11% less paper.
Example 2 – Business cards on B2: B2 (500 × 700 mm), business card finished size 85 × 55 mm + 6 mm bleed = 91 × 61 mm. Portrait: 5 × 11 = 55 units. Landscape: 7 × 8 = 56 units → 56 business cards per sheet.
Example 3 – DIN A6 postcard: A6 finished size 105 × 148 mm + 6 mm = 111 × 154 mm on B2 (500 × 700 mm). Landscape: 4 × 4 = 16 units; portrait: 3 × 6 = 18 units → 18 postcards per B2 sheet.
Sheet Imposition for Offset Printing
Unit size + bleed (3 mm per side) + gripper margin (10–15 mm). B1 sheet (700×1,000 mm): for A5 flyer (150×210 mm) = 3×4 = 12 units. Always optimise orientation (portrait/landscape)! Paper costs often account for 60–70% of total costs.
Frequently Asked Questions (FAQ)
What is a gripper margin and why is it needed?
The press transports the sheet using grippers that clamp the leading edge of the paper. This gripper margin (10–15 mm) cannot be printed and is not available for imposition units. Some printing processes (digital printing, gravure) do not require a gripper margin.
What is the difference between the cut format and the finished format?
The finished format is the desired final size of the printed product. The cut format = finished format + bleed (3 mm per side). The bleed ensures that no white borders appear when cutting, even if the cut is slightly offset.
Does the calculator account for ink sequence or varnish?
No — the imposition calculator is limited to the geometric sheet layout. For work-and-turn (double-sided printing), coating, or spot colours, separate considerations are required that go beyond the area calculation.
