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Resize Image to A4 Size Online Free

Choose DPI and orientation — resize any photo or image to exact A4 pixel dimensions for print or PDF

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A4 Image Dimensions at Every DPI

A4 is 21×29.7 centimeters (8.27×11.69 inches). The pixel size depends entirely on DPI — the same physical A4 sheet needs a different number of pixels depending on whether you are printing it at home, at a photo lab, or displaying it on screen. The table below covers the four most common DPI values.

DPIPortrait (px)Landscape (px)Best for
72 DPI595 × 842842 × 595PDF screen view, email
96 DPI794 × 11231123 × 794Windows screen, presentations
150 DPI1240 × 17541754 × 1240Office print, documents, forms
300 DPI2480 × 35083508 × 2480Professional print, photo lab

Common A4 Image Use Cases

Printing a photo on A4 paper

To fill an A4 sheet at a photo lab or home printer, use 300 DPI (2480×3508px). This gives a sharp print with no visible pixels at normal viewing distance.

Inserting image into Word or Google Docs

Word and Google Docs use A4 as the default page size. Inserting an image at 150 DPI (1240×1754px) keeps the file small while looking sharp when printed or shared as a PDF.

Creating an A4 PDF

PDF viewers use 72 DPI as the base for A4 — 595×842px. For a PDF that will be printed, use 150 or 300 DPI to ensure print quality is not lost.

Scanning and re-saving at A4

Scanned documents are often saved at non-standard sizes. Resize to A4 at your target DPI to standardize the dimensions before archiving or printing.

A4 vs Other Paper Sizes

SizeDimensions (cm)At 300 DPI (px)Common use
A329.7 × 42 cm3508 × 4961Posters, large format
A421 × 29.7 cm2480 × 3508Standard documents
A514.8 × 21 cm1748 × 2480Booklets, flyers
US Letter21.59 × 27.94 cm2550 × 3300US standard documents

Related Tools

Frequently Asked Questions

What is A4 size in pixels at 300 DPI?

A4 (21×29.7 cm) at 300 DPI is 2480×3508 pixels in portrait orientation. At 150 DPI it is 1240×1754 pixels. At 72 DPI it is 595×842 pixels — the standard PDF screen size.

What is A4 in pixels at 150 DPI?

A4 at 150 DPI is 1240×1754 pixels (portrait). This is the standard size for inserting A4 images into Word documents and Google Docs for printing on a home or office printer.

What is A4 at 72 DPI?

A4 at 72 DPI is 595×842 pixels — the standard PDF page size used by Adobe Acrobat, macOS Preview, and most PDF viewers. Use 72 DPI for screen-only PDFs and presentations.

Is A4 the same as US Letter?

No. A4 is 21×29.7 cm (8.27×11.69 inches). US Letter is 8.5×11 inches (21.59×27.94 cm). A4 is slightly taller and narrower than Letter. Use the Resize Image to Inches tool for US Letter dimensions.

How do I resize an image to A4 for printing?

Select 300 DPI in the tool above, keep Portrait orientation, and click Resize Image. The output will be 2480×3508 pixels — the exact size for printing at A4 at professional print quality.

Is my image uploaded to a server?

No. All resizing happens entirely in your browser using the Canvas API. Your image file never leaves your device.