A4 Print Size in Pixels at 300 DPI

The conversion from millimetres to pixels

210 mm ÷ 25.4 × 300 ≈ 2480 px. 297 mm ÷ 25.4 × 300 ≈ 3508 px. Those are the numbers print shops expect for a full-bleed A4 at 300 DPI. Some templates round to 2480×3508, others to 2490×3510. Use the partner’s template when it exists.

A3 (297×420 mm) at 300 DPI is 3508×4961 pixels. A5 (148×210 mm) is 1748×2480. Because ISO sizes share a ratio, an A3 crop scaled down is an honest A4 — unlike scaling 16×20 down to 12×18.

A4 is not 8×10 or US Letter

8×10 inches is 203×254 mm and a 4:5 ratio. A4 is 210×297 mm. US Letter is 8.5×11 in (2550×3300 px at 300 DPI). None of these match. Stretching a US crop to A4 makes heads look long. Letterboxing adds paper the buyer did not order.

If you sell both markets, keep one focal point and export 8×10 and A4 as two custom ratios. That is how shops avoid a second Photoshop session per painting.

Bleed, printers, and home A4

Home inkjets that “fit to page” shrink your artwork to include a hardware margin. For a true edge-to-edge A4, use a shop that prints full bleed or add bleed if the template asks (often 3 mm). Pixel counts then grow slightly — follow the template, not a generic blog table.

Office “print at 100%” from a 72 DPI screenshot is how A4 photos look like stamps in the corner of the page. Size the file to 2480×3508 at 300 DPI, then print at 100% or “actual size.”

Export A4 from Reopic

Open Studio and add a custom ratio 210 × 297 mm (swap for landscape). Export Artwork. The ZIP folder is named with those millimetres so you can see it is not an 8×10. Free includes three custom ratios a day — enough for A4, A3, and 8×10 on one image. Pro is $33 lifetime.

Worked example: US listing that also ships A4

You sell an 8×10 in the United States and want UK orders. Export 2400×3000 for 8×10 and 2480×3508 for A4 from the same pin. The A4 crop is taller: you will see more floor or sky. Check the signature. If A4 reveals a messy studio edge, clone it or keep A4 as a matted SKU.

In the Etsy variation, name the options “8×10 in (US frame)” and “A4 (210×297 mm)” so buyers do not assume they are interchangeable. Upload the matching production file to your printer for each SKU. A single 8×10 JPEG forced into A4 is how faces look stretched in EU reviews.

Home printers and “fit to page”

Buyers of digital A4 files often print from Preview or Windows Photos with “fit” enabled. That shrinks a correct 2480×3508 file to include the printer’s unprintable margin, then people complain the print is small. Put in the listing: print at 100% / actual size on A4, or use a borderless setting if their hardware supports it.

If you sell a physical A4, you control the press. If you sell a download, you control the instructions. Either way the file should still be the real A4 pixel box, not a US Letter JPEG renamed A4.

Need A3 as well? Scale the A4 crop up only if the original still has 3508 pixels on the short side after crop. Otherwise export A3 from the original with the same pin — ISO ratios match, but you still need the pixels. A3 at 300 DPI is 3508×4961. A phone JPEG that barely made A4 will not make a sharp A3.

FAQ: A4 print size pixels 300 DPI