What size can my image print at 300 DPI?
Pixels to inches and centimetres at 300 DPI: choose an image on your device to see its size in pixels, the largest size it prints at 300 DPI and at 150 DPI, and whether it fills a 28 × 36 cm t-shirt print area. The image never leaves your browser.
An image prints at 300 DPI up to its size in pixels divided by 300, in inches; multiply by 2.54 for centimetres. A 3000-pixel-wide image prints 10 inches (25.4 cm) wide at 300 DPI and 20 inches (50.8 cm) at 150 DPI, the resolution below which PrintBlob’s designer warns that an image may print blurry. To fill PrintBlob’s default print area of 28 × 36 cm at 300 DPI, an image needs 3307 × 4252 pixels.
How the numbers are worked out
Resolution is pixels per inch of print. The tool divides the image’s width and height in pixels by 300, the resolution PrintBlob makes its print files at, and by 150, the resolution below which its designer warns, and turns the inches into centimetres (one inch is 2.54 cm). It reads the image’s pixels and nothing else: not its file size, and not the DPI value saved in the file, which changes no pixel and so no sharpness.
PrintBlob’s designer does the same sum while a customer places an image: it works out the image’s resolution at the size it is placed on the product, from the print size the shop entered, and warns below 150 DPI before the customer orders.
Pixels to inches at 300 DPI
| Image width | Widest print at 300 DPI | Widest print at 150 DPI |
|---|---|---|
| 600 pixels | 2 in (5.1 cm) | 4 in (10.2 cm) |
| 1000 pixels | 3.33 in (8.5 cm) | 6.67 in (16.9 cm) |
| 1200 pixels | 4 in (10.2 cm) | 8 in (20.3 cm) |
| 2000 pixels | 6.67 in (16.9 cm) | 13.33 in (33.9 cm) |
| 3000 pixels | 10 in (25.4 cm) | 20 in (50.8 cm) |
| 4000 pixels | 13.33 in (33.9 cm) | 26.67 in (67.7 cm) |
| 5000 pixels | 16.67 in (42.3 cm) | 33.33 in (84.7 cm) |
What fills PrintBlob’s default print area
The front of the t-shirt that comes with PrintBlob prints 28 × 36 cm. To fill it, an image needs 3307 × 4252 pixels at 300 DPI, or 1654 × 2126 pixels at 150 DPI. An image of another shape fills the area only with part of it outside: the designer shows the print area as a dashed line, and nothing outside it is printed.
Questions
How large can you print a 300 DPI image?
As many inches as its pixels divided by 300, on each side. An image of 3000 × 2000 pixels prints 10 × 6.67 inches (25.4 × 16.9 cm) at 300 DPI. Printed larger, each pixel covers more of the print and the resolution falls below 300 DPI.
How many inches is 3000 pixels at 300 DPI?
10 inches, which is 25.4 cm: 3000 divided by 300. At 150 DPI the same pixels cover 20 inches (50.8 cm). The table above gives other common widths.
What does 300 DPI mean?
Dots, here pixels, per inch of print. At 300 DPI every inch (2.54 cm) of the print takes 300 pixels of the image. PrintBlob makes its print files at 300 DPI at the print area’s real size.
Is 150 DPI good enough for a t-shirt print?
150 DPI is where PrintBlob’s designer draws the line: at 150 DPI or more it says the image prints sharp, below it it warns that the image may print blurry. Between the two the print file is still 300 DPI, with the image enlarged to fill it, so fine lines and small text soften first.
Does a bigger file mean a sharper print?
No. Only the image’s width and height in pixels decide how large it prints sharp. A heavily compressed photo can be a large file and still be small in pixels, and a crisp logo can be a small file.
Can I make a small image print sharper by enlarging it?
Enlarging an image in an editor adds pixels but no detail, so it prints as soft as before. Ask for the original file, a larger export, or a vector logo the printer can use.
Is my image uploaded anywhere?
No. The page reads the image’s width and height in your browser and shows them; nothing is sent to printblob.com or anyone else.
Which print area does the tool check?
The front of the t-shirt that comes with the free PrintBlob plugin, which prints 28 × 36 cm. On a shop’s own products, set up with PrintBlob Pro, the designer measures every image against that product’s own print size.
Try it on a product
Upload the same image in the live designer and resize it on the t-shirt: the note under it changes from “Prints sharp” to a warning below 150 DPI. For the size each placement on a t-shirt needs, read What size should a t-shirt design be?; for what makes a file print well, Print-ready t-shirt files and Print areas and print sizes: measure your products and set each side; for how a live mockup saves proof emails, Artwork approval for custom prints: a live mockup or emailed proofs.