What size is my PDF, and how big can I print it?

Why your phone cannot tell you this

A PDF stores its page size in points, seventy-two to the inch, written into the file itself. It is not a guess and it does not depend on your screen. But no PDF reader on a phone shows it, and zooming tells you nothing — a business card and an A0 poster look identical when both fill the screen. That is why a file someone downloaded and forwarded on is a mystery until something reads it properly.

Page size and resolution are two different questions

People ask “what dpi is this PDF” and the honest answer is often that the question does not apply. Resolution belongs to photographs and scans, not to pages. A PDF drawn entirely from vectors — a logo, a typeset flyer, most things that came out of design software — has no resolution at all. It prints at any size, from a sticker to a building wrap, and stays crisp.

When there is a photograph inside, its sharpness depends on how large it was placed on the page, not just on its pixel count. A six megapixel photo is superb across a business card and marginal across an A1 poster. This tool measures the largest image on the page at the size it actually sits, which is the number that decides what you can do with the file.

What the sizes in the table mean

Print is not a single standard. A business card is read at arm’s length and needs to hold up to a hard look; a shopfront sign is read from across a road and never will be. So the largest sensible print size depends entirely on what you are making:

• 300 dpi — business cards, flyers, brochures. Held in the hand and inspected.
• 150 dpi — posters and banners. Read from a metre or two away.
• 120 dpi — corflute signs and A-frames. Read from the footpath.
• 100 dpi — shopfront and vehicle signage. Read from across the street, often while moving.

A file that falls short at 300 dpi is not a bad file. It is a file for a different job. The table tells you which, and every one of those jobs is something we print — see products and prices for what each costs at each size.

If the answer is not what you hoped

A PDF that is too small to print at the size you want has three routes out. Ask whoever made it for the original artwork, which is usually vector and usually solves it outright. Print it smaller, at a size the table says it holds. Or send it to the desk and we will tell you honestly what it will look like before anything runs — and you will see a proof either way, because nothing goes on a press here until you have approved one.

Nothing is uploaded

The file never leaves your device. It is opened and measured by your own browser, the same as every free tool on this site, which is why this works on a document you would not want to email to a stranger. See our privacy policy for what we do and do not collect.