How to Check PDF Margins and Bleed Before Printing
A print job can fail over a few millimetres: text trimmed off, a white sliver along the edge, a logo too close to the fold. You can catch these problems before you hit send by measuring the PDF itself.
Margins, safe area and bleed explained
- Trim size: the final size of the printed piece after cutting.
- Bleed: artwork that extends past the trim edge so no white shows if the cut is slightly off. A common amount is 3 mm (about 0.125 inch) on every side, but always confirm with your printer.
- Safe area (safe margin): an inner boundary where text and key graphics should stay, often 3 to 5 mm inside the trim edge.
Example: A4 with bleed
An A4 flyer is 210 x 297 mm. With 3 mm bleed on each side, the PDF page should be 216 x 303 mm. If your PDF page measures exactly 210 x 297 mm, it has no bleed, even if the artwork looks like it touches the edges.
How to check with a PDF ruler
- Open the file in PdfRuler and set the unit to mm.
- Read the page size from the status bar to confirm trim size plus bleed.
- Enable rulers on all four sides and hover near an edge to read its offset. For example, text that begins at X = 8 mm on a page with 3 mm bleed sits 5 mm inside the trim line.
- Turn on the grid overlay to see whether elements align with a consistent margin.
Checklist before you send to print
- Page size equals trim size plus bleed on each side.
- Backgrounds and images extend all the way to the bleed edge.
- Text and logos stay inside the safe area.
- Units match what your printer asked for (mm vs inches).
Not sure what size you are dealing with? See how to find a PDF's page size and how to measure a PDF online.
Frequently asked questions
How much bleed do I need for printing?
The most common bleed is 3 mm (0.125 inch) on every side, but check your printer's specification.
How do I know if my PDF has bleed?
Compare the PDF page size to the intended trim size. If the page is larger by the bleed amount on each side, it includes bleed.
