Calculating bleed involves extending your design beyond the intended trim size to ensure no white edges appear after cutting. Here's how to calculate it:
Understanding Bleed
Bleed is the area of your design that extends beyond the final trim size. It's a printing industry standard to prevent unprinted edges when the printed piece is cut down to its final size. Without bleed, slight variations in the cutting process can result in unwanted white borders.
Calculating Bleed: The Standard Approach
The standard amount of bleed is generally:
- 0.125 inches (1/8 inch) on each side
- 3 mm on each side
Step-by-Step Calculation
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Determine the Final Trim Size: Identify the desired finished size of your document (e.g., business card, brochure, poster). Let's say we're creating a business card with a final size of 3.5 inches x 2 inches.
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Add the Bleed: Add the standard bleed amount (0.125 inches or 3mm) to each side of the trim size dimensions.
- Width: 3.5 inches + 0.125 inches (left side) + 0.125 inches (right side) = 3.75 inches
- Height: 2 inches + 0.125 inches (top) + 0.125 inches (bottom) = 2.25 inches
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Bleed Size: Your document's bleed size should be 3.75 inches x 2.25 inches. This is the total size you'll set up in your design software.
Example: Business Card
Let's visualize this with a business card:
| Dimension | Final Trim Size | Bleed Amount Added (each side) | Total Size with Bleed |
|---|---|---|---|
| Width | 3.5 inches | 0.125 inches | 3.75 inches |
| Height | 2 inches | 0.125 inches | 2.25 inches |
Safety Margin (Important!)
While adding bleed is crucial, it's equally important to maintain a "safety margin" inside the trim size. This margin ensures that no critical design elements (text, logos, important graphics) are accidentally trimmed off.
- The safety margin is generally the same size as the bleed: 0.125 inches (1/8 inch) or 3 mm on each side.
To establish the safety margin:
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Subtract the margin amount from the trim size.
- Width: 3.5 inches - 0.125 inches (left side) - 0.125 inches (right side) = 3.25 inches
- Height: 2 inches - 0.125 inches (top) - 0.125 inches (bottom) = 1.75 inches
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Keep all essential elements within the safety area. The safe area is 3.25 inches x 1.75 inches.
In Summary
To calculate bleed, add 0.125 inches (or 3mm) to each side of your document's final trim size. Remember to also consider a safety margin within the trim size to prevent important elements from being cut off. This ensures a professional-looking final product.
