Image Resizer
Resize images to any dimension
100% free. Runs entirely in your browser - your files and data never leave your device and nothing is uploaded to any server.
A4 @ 300dpi selected — upload an image to apply it.
Drag & drop files here
or browse to upload
Supports PNG, JPG, WebP up to 20MB
Processed in your browser - your file never leaves this device.
About this tool
An A4 page at 300 DPI is 2480 by 3508 pixels - the size an image needs to print sharply across a full sheet of A4 paper (210 x 297 mm). It is the right target for posters, flyers, certificates and documents printed at home or by a print shop. Here the image is cropped to that 8.7-megapixel portrait frame. At 150 DPI a print looks fine on screen and visibly soft on paper, which is the usual way A4 prints go wrong.
How to use this tool
- Start from a large imageUse a high-resolution original - a small web image enlarged to A4 will print soft.
- Frame the portrait pagePosition the image inside the 2480 x 3508 portrait frame, leaving margins for any printer border.
- Print at 100%Download a PNG or high-quality JPG and print it at actual size, not "fit to page".
Pixels, DPI and print quality
DPI only matters for printing: it tells the printer how many pixels to place per inch. At 300 DPI, A4 needs 2480 x 3508 pixels; at 150 DPI it needs half that in each direction and will look softer up close. Professional printers may also ask for 3 mm bleed on each side, which makes the image 2551 x 3579 pixels. US Letter at 300 DPI is 2550 x 3300.
Key features
- The exact pixel size for sharp A4 prints at 300 DPI.
- Right for posters, flyers, certificates and art prints.
Common uses
- Posters and flyers.
- Printed certificates and documents.
- Art prints on A4 paper.
Tips for better results
- Ask your printer about bleed.
- Start from a high-resolution source.
- Use PDF or high-quality JPG for print.
Mistakes to avoid
- Printing a 72 DPI web image at A4.
- Forgetting bleed for edge-to-edge prints.
Frequently asked questions
2480 x 3508 pixels (210 x 297 mm at 300 DPI).
At 300 DPI, US Letter is 2550 x 3300 pixels.
No - DPI is print metadata; the pixel dimensions determine quality.
300 DPI is the print standard. At 150 the result looks fine on screen and visibly soft on paper, which is the usual way this goes wrong.
Drop it onto this page. The A4 at 300 DPI preset is already selected, so it resizes straight to 2480 x 3508 pixels and shows the crop before you download.