Reference library

Postcard Size

Compare postcard print sizes including 4 × 6, 5 × 7 and 6 × 9, with 300 DPI pixels, bleed setup and USPS card-size mailing limits.

Last checked: 2026-05-03

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At a glance

The classic postcard print size is 4 × 6 inches, but common postcard sizes also include 5 × 7, 6 × 9 and 6 × 11 inches. At 300 DPI, a 4 × 6 postcard is 1200 × 1800 px before bleed. If the design prints to the edge, add bleed before exporting.

Source confidence: Editorial Last checked: 2026-05-03 Source: USPS Postal Explorer: Physical Standards for Commercial Letters and Postcards Found a spec change? Send correction.

How we calculate this

Methodology and source handling

We convert physical sizes to inches, multiply by the selected DPI/PPI value, and round to whole pixels.

Methodology Editorial policy

Quick answer

Copy-ready answer

152.4 x 101.6 mm

Dimensions and specs

4 × 6	Inches: 4 × 6 in; Millimeters: 101.6 × 152.4 mm; 300 DPI pixels: 1200 × 1800 px; Common use: Standard postcard, compact mailer
5 × 7	Inches: 5 × 7 in; Millimeters: 127 × 177.8 mm; 300 DPI pixels: 1500 × 2100 px; Common use: Larger photo postcard or invitation
6 × 9	Inches: 6 × 9 in; Millimeters: 152.4 × 228.6 mm; 300 DPI pixels: 1800 × 2700 px; Common use: Promotional mailer
6 × 11	Inches: 6 × 11 in; Millimeters: 152.4 × 279.4 mm; 300 DPI pixels: 1800 × 3300 px; Common use: Large direct mail piece

Pixels

Pixel dimensions by DPI

DPI / PPI	Width	Height	Use
72 DPI	432 px	288 px	Screen preview or draft layout check
96 DPI	576 px	384 px	Browser and presentation preview
150 DPI	900 px	600 px	Economy print or larger viewing distance
300 DPI	1800 px	1200 px	Recommended high-quality print target
600 DPI	3600 px	2400 px	Fine line art or specialist production

Formula

For print pixels:

pixels = inches × DPI

For bleed:

full width = trim width + bleed left + bleed right
full height = trim height + bleed top + bleed bottom

Example for a 4 × 6 postcard with 0.125 in bleed:

width = 4 + 0.125 + 0.125 = 4.25 in
height = 6 + 0.125 + 0.125 = 6.25 in
300 DPI pixels = 1275 × 1875 px

Common mistakes

Avoid these print setup mistakes

confusing print size with mailing eligibility

A postcard print size does not automatically guarantee a mailing rate. Check USPS size, thickness, aspect ratio and preparation rules.

ignoring the address side

A beautiful design can fail if the address, barcode or postage area is not clear.

designing at trim size when color reaches the edge

Use bleed if backgrounds or images go to the edge.

Calculator

Calculate pixels and bleed

Enter any DPI to calculate the pixel dimensions for this physical size.

Compare

Compare Postcard Size

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Workflow

Postcard bleed setup

Many U.S. print workflows use 0.125 in bleed on each side. That means the full canvas becomes 0.25 in wider and 0.25 in taller than the trim size.

Trim size	With 0.125 in bleed	300 DPI bleed pixels
4 × 6	4.25 × 6.25 in	1275 × 1875 px
5 × 7	5.25 × 7.25 in	1575 × 2175 px
6 × 9	6.25 × 9.25 in	1875 × 2775 px
6 × 11	6.25 × 11.25 in	1875 × 3375 px

Always follow the printer’s template if it gives different bleed, safe-area or mailing-panel requirements.

Pixels

Postcard pixels by DPI

Size	150 DPI	300 DPI	600 DPI
4 × 6	600 × 900 px	1200 × 1800 px	2400 × 3600 px
5 × 7	750 × 1050 px	1500 × 2100 px	3000 × 4200 px
6 × 9	900 × 1350 px	1800 × 2700 px	3600 × 5400 px
6 × 11	900 × 1650 px	1800 × 3300 px	3600 × 6600 px

Details

USPS card-size reference

For USPS commercial card dimensions, the reference range includes:

Requirement	Minimum	Maximum
Length	5 in	9 in
Height	3.5 in	6 in
Thickness	0.007 in	0.016 in

USPS also distinguishes card, letter and flat categories. A design size that prints like a postcard may not always qualify for a specific postcard mailing rate or preparation category.

Guidance

Mailing panel and safe area

For mailed postcards, leave room for:

recipient address;
return address;
postage or indicia;
barcode / automation area;
printer marks or production tolerances;
safe margin around important text.

Do not place critical design elements where the address, barcode or postal markings may go.

Details

Which postcard size should you choose?

Choose 4 × 6 for a compact, familiar postcard.

Choose 5 × 7 for a more premium photo-card feel or invitation-style mailer.

Choose 6 × 9 for more promotional space while staying manageable.

Choose 6 × 11 for high-impact direct mail when the mailing method and printer support it.

Related pages and tools

related Print Sizes related Flyer Print Size related Business Card Print Size related Direct Mail Print Size related Print Bleed and Safe Area tool Print Bleed Calculator tool DPI Calculator tool Compare Sizes

Same branch

Nearby pages

Bleed Print Size Brochure Print Size Business Card Print Size Flyer Print Size Banner Print Size Booklet Print Size Catalog Print Size Direct Mail Print Size

FAQ

Common questions

What is the standard postcard size?

A common standard postcard print size is 4 × 6 inches.

What size is a 4x6 postcard at 300 DPI?

A 4 × 6 postcard is 1200 × 1800 px at 300 DPI before bleed.

What size is a 4x6 postcard with bleed?

With 0.125 in bleed on every side, a 4 × 6 postcard becomes 4.25 × 6.25 in, or 1275 × 1875 px at 300 DPI.

What are USPS postcard dimensions?

For USPS commercial card dimensions, the minimum is 5 in long, 3.5 in high and 0.007 in thick. The maximum card dimensions are 9 in long, 6 in high and 0.016 in thick.

References

Sources and references

Commercial print dimensions are checked against reputable print-provider references. Bleed guidance follows Adobe and printer setup recommendations; final requirements should be confirmed with the printer.

Last checked: 2026-05-03