Most print on demand sellers find out their file resolution was wrong after the proof comes back blurry, not before. That's backwards, and it's an easy problem to prevent once you know what the numbers on the upload screen actually mean.
The short answer
Set your print file to 300 DPI at its final print size and save it as a PNG with a transparent background in sRGB color. That single combination clears the file requirements for the overwhelming majority of print on demand products, from DTG shirts to mugs to phone cases.
For most print on demand sellers, build every design at 300 DPI in PNG format; drop to 150 DPI only for oversized products like blankets, tapestries, or all over print leggings, where your print provider's own guidelines say a lower DPI is acceptable. Check the specific product's file requirements before you upload if you're not sure which category it falls into.
What DPI should a print on demand design file be?
Set it to 300 DPI at the final print size, and you'll clear almost every provider's minimum with room to spare. That's not one universal legal requirement, it's a safe target that sits above what any mainstream provider actually asks for on a standard product.
The real numbers vary by provider and by product. Printify's help center recommends 300 DPI for JPEG and PNG uploads, but notes that a lower resolution file can still be fine depending on the product. Printful's file prep guidance sets the bar lower for most direct to garment apparel: at least 150 DPI, while products like phone cases and stickers need the full 300 DPI. Large format items like leggings, blankets, and tapestries get the most slack, with 120 to 150 DPI treated as acceptable because the print area is large enough that the eye doesn't resolve individual pixels at normal viewing distance.
Build at 300 DPI anyway, even on a product where 150 DPI would technically pass. It costs you nothing but file size, and it means you never have to re-create artwork because you want to reuse it on a product with a stricter requirement later.
What's the difference between DPI and pixel dimensions?
DPI and pixel dimensions are two different measurements, and mixing them up is the single most common file prep mistake in print on demand. Pixel dimensions are the fixed width and height of your file, like 3,600 by 3,600 pixels. DPI is a ratio: how many of those pixels get packed into each inch of the physical print.
That means the same file can be 300 DPI on one product and 150 DPI on another, depending only on how large the design prints. A 3,600 by 3,600 pixel file prints at 300 DPI on a 12 inch wide design (3,600 ÷ 300 = 12), and at 150 DPI if that same file gets stretched to print at 24 inches wide (3,600 ÷ 150 = 24). The file didn't change. The print size did, and the effective sharpness dropped because the same number of pixels is now covering twice the area.
This is why "is my file high enough resolution" only has an answer once you know the print size. A 1,000 by 1,000 pixel logo is plenty sharp for a 2 inch chest print (500 DPI) and noticeably soft on a 12 inch back print (83 DPI).
Should a print on demand file be PNG or JPEG?
Use PNG for almost every design you prepare for print on demand. The deciding factor is transparency: PNG supports a transparent background, and JPEG does not.
Direct to garment printing needs that transparency so the shirt's actual color shows through around your artwork instead of printing a solid rectangle behind it. A JPEG saved from a design tool with a "transparent" looking background usually isn't actually transparent, it's been flattened onto white, and that white shows up as a visible box once it hits a colored garment. Printful's own file prep guidance calls this out directly: JPEG files don't support transparency, so a design meant to sit directly on the fabric should be a PNG.
JPEG still has a place for photographic imagery where there's no transparency involved at all, like a full bleed poster or an all-over sublimation print that covers the entire product. For a shirt, hoodie, or tote where your artwork sits on a colored blank, PNG is the format, full stop.
Does the background need to be fully transparent?
Yes, and check the edges, not just the obvious background area. A design with semi-transparent pixels along the edge of text or linework, left over from a soft eraser brush or an anti-aliased selection, can print as a faint halo or fringe around the artwork. Printful's guidance specifically flags checking for leftover semi-transparent pixels and stray marks before upload, since they're invisible on a white canvas in your design software and very visible once printed on a colored shirt.
Zoom in on your file's edges before exporting. A quick way to check: temporarily place a bright color behind your design layer in your editor and look for any faint shapes that shouldn't be there.
RGB or CMYK: which color profile should I use?
Use sRGB. Printful is explicit about this: it asks for sRGB IEC61966-2.1 and handles the conversion to its printers' actual color space internally, so submitting a CMYK file doesn't give you more control, it just risks a color shift if the provider's software interprets it differently than you expect. Printify's own help documentation doesn't publish a required color profile at all, and tells sellers to check the specific file requirements shown for each product inside its Product Creator.
The practical rule: design in sRGB unless a provider's own file guidelines explicitly ask for something else, and don't convert to CMYK on your own assuming it'll produce a more accurate print. Most consumer design software, including Canva, Procreate, and the standard export settings in Photoshop and Affinity, already defaults to sRGB, so for a lot of sellers there's nothing extra to do here beyond not changing it.
Specs at a glance
| Setting | Target | When it can be lower | Source |
|---|---|---|---|
| DPI (most DTG apparel) | 300 DPI | 150 DPI minimum accepted by Printful | Printful file prep guidance |
| DPI (large format: leggings, blankets, tapestries) | 300 DPI | 120 to 150 DPI accepted | Printify, Spring help docs |
| DPI (phone cases, stickers, posters) | 300 DPI | Not recommended to go lower | Printful, Printify |
| File format | PNG with transparency | JPEG only for full-bleed, no-transparency art | Printful file prep guidance |
| Color profile | sRGB IEC61966-2.1 | Only switch if a provider's own guide asks for something else | Printful |
| Max file size (Printful) | Up to 200 MB, 20,000 x 20,000 px | - | Printful |
| Max file size (Printify) | 100 MB (JPEG/PNG), 20 MB (SVG) | - | Printify |
Specs above summarize published Printful and Printify guidance as of this writing. Both providers show exact requirements per product inside their own upload tools, and those numbers can change, so treat this table as a starting point and confirm against the live file guidelines before you submit an order.
What actually happens if your file is too low resolution?
The print gets stretched to fill the print area regardless of how many pixels you gave it, and the shortfall shows up as soft edges, blurry fine text, and visible pixelation, especially along curves and thin lines where there aren't enough pixels to render a clean edge. Bold, simple shapes hide a resolution shortfall better than small text or fine linework does, which is why a low-res file can look fine as a thumbnail and then look rough once it's printed at 12 inches across a chest.
Most providers will warn you in the upload tool if a file falls under its resolution threshold for the selected print size. That warning is useful, but it's an estimate based on pixel count and print area, not a guarantee. Dismissing the warning and ordering anyway means you're accepting the risk, not proving the file is actually fine.
Does your mockup image need the same resolution as your print file?
No, and conflating the two leads a lot of sellers to either over-prepare mockups or under-prepare print files. The print file's job is to survive being printed onto fabric at full size, which is why it needs real pixel density at 300 DPI. The mockup's job is to display correctly on a product listing page at screen resolution, which has completely different requirements: a sharp, reasonably sized JPEG or PNG that looks clean at the dimensions Etsy or Shopify actually displays it.
This is one of the only places it's worth mentioning what we build: Drop Studio takes your print-ready artwork and renders it onto photoreal mockups for your listings, so the file you prepared at full print resolution for your provider and the image your customer sees on the listing page can come from the same source file without you having to manage two separate resolution standards by hand.
Common file prep mistakes to avoid
- Assuming a file is "high resolution" without checking it against the actual print size. A million-pixel file can still be low DPI at a large print size.
- Exporting as JPEG for a design meant to sit directly on a colored garment. The flattened white background will show.
- Leaving semi-transparent edge pixels from an eraser tool or a soft selection, which print as faint halos.
- Converting to CMYK when a provider asks for sRGB, which can shift colors rather than improve them.
- Treating one provider's DPI minimum as universal, when the real number depends on the specific product and that provider's own stated requirements.
- Using the same file resolution standard for a listing mockup as for a print file, when the two have entirely different jobs.
Build your working files at 300 DPI in PNG with a transparent background and sRGB color, and you'll clear the requirements for nearly every product you're likely to sell, with the specific exceptions above being the only cases worth double-checking before you hit submit.
Related reading:
- GSM, Ring Spun, and Combed Cotton: What T-Shirt Specs Actually Mean for Print on Demand
- Etsy and Shopify Image Size Guide for Print on Demand
Sources: Printful, How should I prepare my print file for the best results; Printify, What type of print files does Printify require?. File requirements vary by provider and product, and can change. Always confirm current specs inside your provider's own upload tool before submitting an order.