Resolution and pixel calculator

A photo or bitmap image is made of pixels, tiny squares of colour. Resolution is measured in dpi (dots per inch): how many pixels fit into one inch (2.54 cm) of printed paper. The more there are, the sharper the print.

How many dpi you need

• 300 dpi for anything held in the hand: business cards, flyers, menus, books.
• 150 dpi for posters, usually seen from a metre or two away.
• 100 dpi for banners, roll-ups and signs, seen from a distance.

Viewing distance is what matters: from further away the eye can't pick out single pixels, so a large banner doesn't need the density of a business card.

Enlarging doesn't add quality

If an image is small, stretching it in your software or changing its dpi setting can't create detail that isn't there. The same pixels just get bigger, and the image turns blurry or blocky.

Important. Changing the dpi of a small image in Photoshop does not improve it. Only the number of pixels at the final size matters.

Images from social media and WhatsApp

Facebook, Instagram, WhatsApp and Viber compress photos so they load quickly. They look fine on a phone screen but are rarely good enough for print. Always ask the photographer for the original file, or send it from your phone as a “document”.

Pixel calculator

Pick a size and product to see how many pixels your image needs. Or type in the pixel size of an image you already have to see how large it prints well. Decimals can use a comma or a point.