Here is the answer before the explanation. 300 DPI is the right target for paper, stickers and posters, and roughly twice what a T-shirt can physically resolve. For direct-to-garment apparel, 150 DPI at the finished print size is the honest floor, and the extra pixels above it mostly make your upload slower. And DPI is not a setting inside your file at all — it is your pixel count divided by the inches you are printing across, which is why exporting "at 300" so often changes nothing at all.
The rest of this explains why, gives you the pixel dimensions for every common placement, and covers the three things that actually cause reprints: bleed, transparency and colour.
What DPI should a print-on-demand file be?
DPI is your pixel count divided by the print size in inches, not a setting inside the file. Send 300 DPI at the finished size for paper, stickers and sublimated hard goods. For direct-to-garment apparel, 150 DPI at the finished size is the honest floor, and extra pixels mostly slow the upload.
DPI is a division, not a setting
DPI — dots per inch — is a ratio. It is the number of pixels across your image divided by the number of inches it will be printed across. That is the entire definition.
A file 3,000 pixels wide is 300 DPI printed at 10 inches. The same file is 250 DPI printed at 12 inches, 200 DPI at 15 inches, and something absurd printed on a postage stamp. The pixels never changed. Only the divisor did.
The confusion comes from the fact that design software stores a DPI number in the file's metadata. That number is a note about intended print size, not a property of the image data. Changing it in an export dialogue without resampling changes a label and nothing else, which is why people who "set it to 300" often see no difference.
So "is my file 300 DPI" is not an answerable question. The answerable question is: how many pixels do I have, and how many inches wide will it print?
Which print method your provider uses decides how much of that resolution survives, so this is worth settling at the same time as choosing a print provider — sublimation, direct-to-film and direct-to-garment do not hold the same detail on the same artwork.
Where 300 DPI came from, and where it still belongs
300 DPI is a print trade convention for paper. Ink sits on a smooth coated surface, and the eye at reading distance stops resolving detail somewhere around that density. For paper it is a sensible, well-earned standard.
It is the right target for stickers, greeting cards, art prints, posters, packaging inserts and anything sublimated onto a hard coated surface such as a mug, a coaster or a metal sign. For those products, send 300 DPI at the finished size and do not argue with it. The mistake is carrying the number across to fabric, where the physics are different.
What direct-to-garment can actually resolve
A T-shirt is not paper. It is a knitted structure of yarn with gaps in it, and direct-to-garment printing sprays water-based ink that soaks into and travels along the fibres. The ink wicks sideways by a small but real amount as it lands, and the surface itself has a texture coarser than the detail you are trying to place on it.
That gives fabric a physical ceiling on detail well below what 300 DPI describes. In practice, 150 DPI at the finished print size is the honest floor for direct-to-garment work, and going far above it buys you very little you can see on the shirt. The extra pixels mostly make your file heavier and your provider's software work harder before it downsamples them anyway.
One honest caveat: hard edges hold up better than soft ones. Fine line work and small type do gain something from extra resolution in a way a painterly design does not, so 200 to 250 DPI is a reasonable compromise for crisp vector-style work. For anything textured or photographic, 150 is genuinely enough. And if your art started as vector, the question disappears — export at whatever pixel dimensions you need.
The pixel dimensions, worked out
Print areas vary between providers and between garment sizes, so treat these as the usual case and check the specific product page before you build a template. To go the other way from a print size you have already chosen, work out the design size for a placement rather than doing it in your head.
| Placement | Print size (inches) | Pixels at 150 DPI | Pixels at 300 DPI |
|---|---|---|---|
| Adult tee, full front | 12 × 16 | 1800 × 2400 | 3600 × 4800 |
| Adult tee, standard front | 11 × 14 | 1650 × 2100 | 3300 × 4200 |
| Left chest | 4 × 4 | 600 × 600 | 1200 × 1200 |
| Sleeve | 4 × 14 | 600 × 2100 | 1200 × 4200 |
| Hoodie front, above the pouch | 10 × 12 | 1500 × 1800 | 3000 × 3600 |
| Tote bag | 12 × 14 | 1800 × 2100 | 3600 × 4200 |
| Mug wrap, 11 oz | 8.5 × 3.5 | 1275 × 525 | 2550 × 1050 |
| Round sticker | 3 × 3 | 450 × 450 | 900 × 900 |
Read that table as two groups. The garments are fine anywhere from the 150 column upward. The mug and the sticker belong in the 300 column, because sublimation onto a coated surface and vinyl printing both hold detail that fabric cannot.
One thing the table hides: a small and a 3XL usually do not share a print area. A design built to fill the 3XL gets scaled down on the small, so build to the size you expect to sell most of.
Bleed, and when you actually need it
Bleed is extra artwork extending past the line where the material will be cut, so that a cut landing a millimetre off does not leave a white sliver at the edge. Most print-on-demand sellers never need it. A chest print on a tee has no edge to bleed to — the design floats in the middle of a garment that was cut and sewn before your file arrived.
It matters when ink meets the edge of the material: die-cut and kiss-cut stickers, all-over-print garments, cut-and-sew products, cushion covers, mugs that wrap the full circumference, and posters trimmed to size. For those, the convention is 3 mm — an eighth of an inch — of artwork past the cut line, with a safe area the same distance inside it where nothing important sits.
On a garment, the safe area is about placement tolerance
Garments are loaded onto a platen by a person. Placement varies by a fraction of an inch on a good day and by more on a bad one. Keep critical elements away from the outer boundary of the print area: if your text runs to the last quarter inch, a print that lands slightly low puts it under the hem on a small.
Remember too that seams, zips, pocket stitching, collar bands and the hoodie pouch edge are not printable. Direct-to-garment needs a flat surface under the print head, so anything raised either gets avoided or produces a gap in the print.
Transparency, and why a JPEG cannot carry it
The JPEG format has no alpha channel. It has no way to record "nothing here". Every pixel must be given a colour, so the space around your design becomes white — and on a black shirt that is a white rectangle, printed, on the shirt you sent to a customer. Save as PNG with a genuinely transparent background. That is the whole reason PNG is the standard in this industry.
Two subtler traps sit behind that one.
Semi-transparent pixels. On a dark garment the printer lays a white underbase in the shape of your non-transparent pixels, then prints colour on top. A drop shadow fading gradually to nothing hands the machine a fading underbase, which comes out as a grey haze with a ragged edge. Anti-aliasing on the edge of type is fine and necessary. A two-hundred-pixel gradient fade to transparent is a different thing, and it will not look the way it looks on your screen.
White in the artwork on a white garment. On white and very light garments, providers commonly print without a white underbase, and white areas in your design are simply the garment showing through. A white outline you drew to separate two shapes will therefore vanish. This behaviour varies, so confirm it with your provider rather than assuming either way.
Flatten before you export. Hidden layers, adjustment layers, clipping masks and smart objects are tools for you, not instructions for a printer.
Colour, and why your saturated blue prints dull
A screen makes colour by emitting light. A print makes colour by absorbing some wavelengths and reflecting the rest. The set of colours each can produce is different, and at the bright, saturated end the screen's set is considerably bigger.
Saturated blue is the classic casualty. Pure blue on an sRGB display is vivid and faintly electric. No CMYK ink set reproduces it, so the printer's software maps it to the nearest colour it can mix, which is darker, flatter and often leans slightly purple. Bright orange, neon green and hot pink go the same way.
So choose the compromise yourself. Pull the saturation back until the on-screen colour is one you would be happy to receive in the post, rather than leaving that decision to a conversion you never see. A slightly duller blue that you picked beats a slightly duller blue the machine picked, because you got to adjust everything around it to match.
Design in sRGB and send sRGB. Most print-on-demand pipelines expect it and convert to their own device profile on receipt. Converting to CMYK yourself first usually makes things worse, because you are guessing at a profile you do not have. Send CMYK only if the provider explicitly asks for it. Garment colour matters here too: printing onto a coloured garment without a full white underbase lets the shirt colour show through the ink, so the same file on heather grey and on black is two different results.
The export settings to hand a provider
- Decide the finished print size in inches first. Everything else is derived from it.
- Multiply those inches by your target density — 150 for garments, 300 for paper, stickers and sublimated hard goods.
- Build or scale the artwork to that pixel size. Do not upscale a small file to hit a number; you are inventing pixels, not adding detail.
- Flatten to a single layer over a transparent background.
- Export PNG-24, which is PNG with eight bits per channel plus alpha. Not PNG-8, which is limited to 256 colours and will band your gradients. Not JPEG, ever, for anything with a background.
- Embed the sRGB profile, then check the print file before you upload it fifty times over.
- Name the file something you will recognise in six months.
Worth saying plainly: a technically perfect file on a listing nobody finds still sells nothing. Once the artwork is right, the next lever is the thirteen Etsy tags that decide which searches the product is even eligible for.
What to do next
Two things, in this order, before you export anything else.
Open the design size calculator and put in the print size in inches for your main placement. It returns the pixel dimensions you should be building at, at both densities, so you are working to a number rather than a habit.
Then run the finished PNG through the print file checker. It reports the actual pixel dimensions, the colour mode and whether the transparency survived your export — which catches the two failures behind most reprints: a file smaller than the space it has to fill, and a background that is white rather than absent.
Decide the inches, multiply by a density appropriate to the material, and keep the background empty. The number 300 was never the target. The finished size always was.