Print Size Calculator
Enter a physical size and DPI to get the exact pixel dimensions your print-on-demand design needs. Pick a preset for a t-shirt, poster, mug, or sticker, or type your own. Free, no signup, nothing leaves your browser.
Design your file at
3,600 × 4,800 px
Or pick a common print area:
Pixels = inches × DPI. Design at 300 DPI for apparel and prints so the artwork stays sharp. Export a transparent PNG for anything printed on a garment. Exact maximum print areas vary by print provider, so treat these presets as safe starting sizes and check your provider's template for the final canvas.
Sharp prints, every time
Size your file to the print area at 300 DPI from the start, so the artwork never comes out soft or pixelated.
Every product covered
Presets for t-shirts, hoodies, posters, mugs, stickers, and totes, plus a custom mode for any size in inches or centimetres.
100% private
Runs entirely in your browser. No account, no email, nothing sent to a server.
Common print sizes at 300 DPI
These are safe starting canvases for the most common print-on-demand products. Exact maximum print areas vary by provider, so always confirm against your print partner's template, but designing at these dimensions at 300 DPI keeps your artwork crisp.
| Product | Physical size | Pixels @ 300 DPI |
|---|---|---|
| T-shirt front (standard) | 12 × 16 in | 3,600 × 4,800 px |
| T-shirt full front (oversized) | 15 × 18 in | 4,500 × 5,400 px |
| Hoodie front | 12 × 14 in | 3,600 × 4,200 px |
| Poster (small) | 12 × 18 in | 3,600 × 5,400 px |
| Poster (large) | 24 × 36 in | 7,200 × 10,800 px |
| Mug wrap | 9 × 3.5 in | 2,700 × 1,050 px |
| Sticker | 3 × 3 in | 900 × 900 px |
The one rule: pixels = inches × DPI
Everything above comes from a single formula. Multiply the physical size in inches by the resolution in dots per inch, and you get the pixel dimensions your file needs. A 12-inch print at 300 DPI is 3,600 pixels. Design smaller than that and the print looks soft, because there are not enough pixels to fill the space. Scaling a small image up afterwards does not add real detail, so it is always better to start large.
Getting the size right is step two
A crisp file matters, but it only pays off if people actually want the design. The bigger decision comes first: picking a niche with real demand and competition a new shop can beat, before you open your design software at all.
That research is what Trendlytic is for. It shows what is genuinely selling across Etsy, Redbubble, TeePublic, and Amazon Merch in one search, scored for demand and competition, with a live USPTO trademark check on every keyword so you don't build on a phrase you can't use. $5/month for 100 searches, free trial, no card.
Frequently asked questions
What size should a t-shirt design be?
For a standard adult front print, design on a canvas around 12 × 16 inches at 300 DPI, which is 3,600 × 4,800 pixels. A popular oversized full-front canvas is 4,500 × 5,400 pixels (15 × 18 inches at 300 DPI). Always export a transparent PNG. Exact maximum print areas vary by print provider, so check your provider's template, but designing at 300 DPI at these sizes keeps you safe.
How do I convert inches to pixels for printing?
Multiply the physical size in inches by the DPI (dots per inch). Pixels = inches × DPI. So a 12-inch-wide design at 300 DPI is 3,600 pixels wide. This calculator does that for width and height at once, and also handles centimetres by converting them to inches first (1 inch = 2.54 cm).
What DPI should print-on-demand designs be?
300 DPI is the standard for apparel and art prints, because it stays sharp when printed at full size. Large-format posters viewed from a distance can sometimes use 150 DPI, but 300 DPI is the safe default. Lower than 150 DPI risks a blurry or pixelated print.
What is the best file format for print-on-demand?
A transparent PNG is the standard for designs printed on garments, because the background needs to disappear. Posters and wall art are often supplied as high-resolution PNG or PDF. Whatever the format, the pixel dimensions (size × DPI) matter more than the format itself for print sharpness.
Does image size affect print quality?
Yes. If a file has too few pixels for the physical size you print it at, the print looks soft or pixelated. That is why you size the file to the print area at 300 DPI from the start. Scaling a small image up later does not add real detail, so it is always better to design large.
Is this print size calculator free?
Completely free, with no account and no sign-up. It runs entirely in your browser, so nothing you enter is sent to a server. Enter a size, pick a DPI, and read the pixel dimensions instantly.