How to export a PDF from Adobe Indesign with correct trim box dimensions

Document Setup

When creating a new document:

1. File → New → Document
2. Set:
   • Page Size: A5
     • 148 mm × 210 mm (Portrait)
     • or 210 mm × 148 mm (Landscape)
3. Expand Bleed and Slug
4. Enter:
   • Top: 3 mm
   • Bottom: 3 mm
   • Inside: 3 mm
   • Outside: 3 mm

Click Create.

You should now see:

• Black page edge = Trim size (A5)
• Red guide = Bleed edge (3 mm outside trim)

Prepare Artwork

Extend any background colours, images, or graphics that touch the edge of the page all the way to the red bleed guide.

Export PDF

1. File → Export
2. Choose Adobe PDF (Print)
3. Click Save

PDF Export Settings

General

Choose a preset such as:

• PDF/X-4 (recommended by many printers)
• PDF/X-1a (if specifically requested)

Marks and Bleeds

1. Select Marks and Bleeds
2. Tick:
   • Use Document Bleed Settings
3. Tick
   • Crop Marks if requested by your printer