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Print Margin and Bleed Size Calculator

Calculate bleed document dimensions, text area, and margin ratios for professional print design in any document size.

Finished/trim document width. A4 = 210 mm, A5 = 148 mm.
Finished/trim document height. A4 = 297 mm.
Standard bleed: 3 mm each side for commercial printing.
Inside (gutter) margin -- wider for bound documents to prevent text disappearing into the spine.

Results

Bleed Document Width216.0 mm bleed width
Bleed Document Height303.0 mm bleed height
Text Area Width170.0 mm text area width
Text Area Height257.0 mm text area height
Text Area Coverage70.0%

📖What is it?

Bleed is an extension of background artwork beyond the trim edge so that when the printer cuts the paper, there is no risk of a white gap appearing at the edge. Margins define how close text and important elements are to the trim edge. The gutter (inside margin) must be wider for bound documents to compensate for pages curving into the binding.

🎯How to use

Enter your finished (trim) document size, bleed amount per side, and margin values. The calculator outputs the total document size with bleed (what you set in InDesign/Affinity as your document dimensions), the live text area dimensions, and percentage of the page used for text.

💡Example scenario

An A5 book page (148x210 mm) with 3 mm bleed: set document to 154x216 mm in your DTP app. With 25 mm gutter, 15 mm outside, 20 mm top/bottom, the text area is 108x170 mm = 1836 mm2 = 59% of the page area.

🏆Pro tip

Keep all critical content at least 3-5 mm inside the trim edge -- this is the safe zone. Printer crop marks and registration marks are placed outside the bleed. For saddle-stitch booklets, creep causes innermost pages to shift outward after folding -- increase gutter margin by approx 1 mm for every 16 pages of total book thickness.