Every design in Alomations comes back print-ready: a transparent PNG at 12 inches and 300 DPI, which is 3,600 pixels on the long side, with an SVG alongside, in a light and a dark version. That set gives a production partner a sharp file that fits inside the front print areas providers publish, leaves the shirt colour showing wherever there is no ink, and lets each garment colour get the version that reads on it.
This is for sellers who are new to print files and want to know what they are getting, and whether anything needs changing before an order goes to print. If you print some orders yourself, you work from the same files, so knowing why each part is there saves guesswork at the heat press.
What each design comes back as
Here is the full spec in one place:
| Part | What you get | Why it matters for apparel |
|---|---|---|
| Size | 12 inches on the long side | Fits inside the front print areas providers publish for adult tees |
| Resolution | 300 DPI | The resolution providers recommend for PNG print files |
| Pixels | 3,600 on the long side | 12 inches times 300 DPI, so the DPI holds at full size |
| Format | PNG | Supports transparency, the usual choice for DTG and DTF files |
| Background | Transparent | Areas without artwork print nothing and show the shirt |
| Second file | SVG alongside | A second format for tools and products that take SVG |
| Versions | Light and dark | One reads on dark garments, the other on light ones |
The rest of this article explains each line.
Why 12 inches at 300 DPI
DPI only means something next to a physical size. A file is 300 DPI at 12 inches because it has 3,600 pixels across that length. Printed larger, the same pixels spread out: at 15 inches wide, 3,600 pixels give 240 DPI. That is why print providers ask you to size the file to the actual print dimensions, so the DPI is calculated correctly.
300 DPI is the figure providers recommend for raster files. One provider gives 300 DPI as the recommended resolution for JPEG and PNG files, with large-format products needing less, and another asks for 150 to 300 DPI depending on the product. A file at 300 DPI meets the top of those ranges at its full size. Our explainer on what DPI means for print files covers the maths.
Twelve inches on the long side sits inside the front print areas providers publish. One large provider's older standard front area was 12 x 16 inches, and it now uses 15 x 18 inches on select DTG tees. Other providers differ, so check the template for the product you sell. Our guide to t-shirt print areas compares front, back, sleeve and pocket sizes.
Why a PNG with a transparent background
A print file has to tell the printer where not to print. PNG can store transparency and JPEG cannot. One provider's file guide says that for DTG products, PNG is usually the best option because it supports transparent backgrounds, and that transparent areas in a JPEG can print as white. On a black shirt, that is a white box around your design.
For DTF, the method our catalog uses for apparel, the design is printed onto a transfer film, coated with adhesive powder and heat-pressed onto the garment. Only the artwork ends up on the shirt, so clean transparent edges matter, and stray half-transparent pixels around a shape are worth cleaning up before print.
One thing a print file is not: a listing photo. Etsy does not support transparent PNG files as listing photos, so your listing shows mockups, and the transparent PNG goes to production.
What the SVG is for
SVG is a format that can describe shapes as paths, which is why vector artwork in SVG scales without the blur a raster image gets when it is enlarged. Having one alongside the PNG gives you a second format for tools, cutters and products that take SVG, and for resizing work. Our guide what is an SVG file explains why a PNG and an SVG of the same design behave differently when scaled.
For flat artwork that you want as true vector shapes, the Design Editor can redraw flat art as vector. Before you upload an SVG anywhere, check the provider's limits: one provider caps uploads at 20 MB for SVG against 100 MB for JPEG and PNG.
Light and dark versions
A single file rarely reads well on both white and black shirts. Every design comes back in a light and a dark version, and tone rules per garment colour decide which version each shirt colour gets. The rules run automatically, and you can override them. The light variant turns lettering white, even where it touches the drawing, so text stays readable on dark fabric. The dark variant keeps painted art and line drawings readable on light shirts.
On dark garments, light colours rely on white ink. DTF carries a white ink layer that lets it work on any fabric colour, which is what lets the light version show up on a black tee. Our article on light and dark versions of a design explains when you need both.
When to look twice at the defaults
The defaults suit a standard adult front print. A few cases call for a second look:
A small left-chest print. The design prints far smaller than 12 inches, so resolution is not the issue: thin lines and small text are. Check that the details still hold at the smaller size.
A larger print area. Across more than 12 inches, the same pixels give a lower DPI. Check your provider's minimum before scaling up.
Uploaded artwork that started small. A low-resolution upload stretched to 12 inches is still soft. The Design Editor can enlarge a photo that is short of pixels, and our guide to print file requirements lists what to check before you upload.
Colour profile. Keep files in RGB. One provider recommends the sRGB IEC61966-2.1 colour profile and warns that converting to CMYK can reduce the colour information available.
Mugs, tumblers and wall art. Each product has its own print area and aspect ratio, so follow that product's template rather than the apparel size.
Where the files go after the run
When an Etsy order arrives in Alomations, the design and variant are already matched, with the buyer's personalization text and photos attached. So whether you send the order to a production partner from the orders screen, with item cost and shipping shown separately before you pay from your balance, or print and ship it yourself, there is no hunting for the right file. For personalized designs, the buyer's text is placed into the design when the order arrives, and a buyer's photo is cropped around faces and detail, and can be redrawn in a look, before the print file is prepared.
Frequently asked questions
Is 300 DPI enough for a print-on-demand shirt?
Yes, for a print at the file's own size. Providers recommend 150 to 300 DPI depending on the product, and 300 DPI at 12 inches meets the top of that range. If you print larger, the DPI drops in proportion.
Why is the background transparent?
So that only your artwork prints. A white or coloured background would print as a box on the shirt. Transparent areas let the shirt colour show through.
Do uploaded designs come back print-ready too?
Yes. Uploaded artwork comes back in the same format as AI-generated designs, but a small upload cannot gain detail it never had. For an image short of pixels, use the Design Editor's enlarge tool (paid plans) and check the result at actual size.
Do I need both the light and the dark version?
Only if you sell the design on both light and dark garments. The tone rules pick the version for each colour automatically, and you can override the choice.
You can see the print-ready files for your own designs on the free plan, no card required.
