Printing on a T-shirt isn’t as simple as printing on paper. It’s a fairly manual process that behaves differently on various fabric types and colors. That’s why artwork that looks great on a computer screen can still be blurry or pixelated on a shirt — it can even print in the wrong color if the design isn’t set up correctly.
Whether you’re trying to print your own shirt or order professionally made custom apparel, you have to prepare for several factors, such as choosing the right file type and packaging it properly, ensuring you have a high-resolution image, choosing the right “kind” of colors, and converting any fonts to shapes that can be understood by any printer.
If you prepare accordingly, you can expect crisp, professional results and eliminate any unnecessary costs or delays.
Here’s what you need to know.
Raster vs. Vector Graphics: What’s the Difference?
One of the most important concepts in T-shirt printing is understanding raster vs. vector artwork. This is often what will determine whether your graphic looks sharp or blurry.
Raster Graphics
Photographs, scanned images, and most web graphics are all raster images, which are graphics made of tiny squares called pixels.
They’re everywhere and are great for most use cases — but the problem is that they’re resolution-dependent. If you enlarge them too much, they get blurry or pixelated. This can be solved by simply using a high-DPI graphic (more on that in a minute).
Common raster file types include:
- JPG / JPEG
- PNG
- GIF
- TIFF
Vector Graphics
Vector artwork is made with mathematical lines, curves, and anchor points. Unlike pixel-based raster images, this construction allows them to scale up or down infinitely without losing quality. This makes them ideal for shirt printing, especially for logos, text, and illustrations with flat color and simple gradients.
Common vector file types include:
- AI (Adobe Illustrator)
- EPS
- SVG
And then there are some file types that you’ll see across both raster and vector graphics. For example, Photoshop (PSD) files primarily contain raster images but can be used for vector art. Conversely, most PDFs are vector-based, but they may be composed of scans or other raster images.
The Secret to High-Quality Raster Prints: Higher DPI
So how do you get a sharp graphic if you don’t have a vector-based version? The answer isn’t just “make it bigger.” After all, you can upscale any graphic, but if there aren’t enough pixels to support it, it’ll just be a blurry mess.
That’s where PPI (pixels per inch) comes in, which refers to the resolution of raster images. These days, you’ll more commonly see the term DPI (dots per inch) — which was historically reserved for referring to how many dots a physical printer can print on a surface — but the two terms have more or less become synonymous.
Here’s where it matters: The human eye can easily detect the granularity of something printed at 72 DPI from just a few feet away, whereas even in close proximity, the human eye interprets 300 DPI as a solid continuous line. There are certainly cases where 150–200 DPI graphics are suitable, such as banners and billboards viewed from a distance. In some cases, 200 DPI can even be used on a shirt. But it’s better to be safe than sorry here and stick to the gold standard of 300 DPI for T-shirts.
Do: Start your design process on a 300 DPI canvas that’s the size of the final intended design (your image editing software or graphic designer can easily set this up).
Don’t: Create your design, then enlarge it or increase the resolution as an afterthought. A small image that’s 300 DPI won’t stay 300 DPI if it’s enlarged to fill a shirt.
Print Color Spaces Explained
Color is one of the most misunderstood factors in physical printing. What you see on your screen is created with light and is called additive color. What prints on a shirt is created with pigments in the form of ink and is called subtractive color. These two systems don’t behave the same way, which is why colors can look different once printed.
RGB (Red, Green, Blue)
- Used for screens, websites, and digital displays
- Brighter, more vibrant color range
- Common in digital artwork and online images
CMYK (Cyan, Magenta, Yellow, Black)
- Used for traditional printing
- Smaller color range than RGB
- Required for some print workflows
Spot Colors (Pantone / PMS)
- Pre-mixed inks that form an exact color that never changes
- Each spot color requires its own screen
- Ideal for brand consistency
Although CMYK is ideal, RGB graphics are completely acceptable for garment printing — you just have to be aware that what you see on your screen will not match the end result. To get an idea of what your design will look like in person, you can change the color mode in your design software from RGB to CMYK. As another option, Photoshop offers a handy “View / Gamut Warning,” highlighting these colors so you can select and adjust them to your liking.
When exact color matches are critical (like for company logos), printing pre-mixed spot colors is the safest choice. These can be purchased from print suppliers or custom-mixed following a color matching system like the Pantone Matching System. There are literally thousands of PMS color options available for color matching, whereas some RGB colors simply can’t be reproduced to match the color you see on your screen.
Embedded vs. Linked Graphics
When you create a design in software like Illustrator, the file you work from doesn’t always contain all of the graphics in the actual image. In many cases (especially if you’re composing a design from several different assets), what you’ve included in the file are just references to a file that lives somewhere else. And if you try to print your design without embedding the asset in the file itself, it might show up as missing, low-resolution, or replaced by an unintended graphic.
To avoid this, always embed all images before sending your file off for printing. You can also package the file with all linked assets included (this will look like a folder with multiple files inside it). Whatever you do, do not attempt to avoid this issue by simply copying and pasting low-res files into your software; that defeats the purpose of using high-quality images.
How to Embed Your Graphics
Adobe Illustrator:
- Select your object
- Go to Window → Links → Hamburger Menu → Embed Image
Adobe Photoshop:
- Select your object
- Layers → Right click → Embed Linked
Converting Fonts to Outlines
Fonts are another frequent source of issues. Although you may have found the perfect font for your design, it’s important to remember that fonts are actual files that live on your computer — and not everyone has access to every single one of your fonts. Most computers only have a few hundred fonts installed by default, and there’s no guarantee that a printer will have your favorite.
If they don’t, your text will change to a different font. It may even reflow, resize, or appear distorted or unreadable.
What you can do is convert your text into a vector shape that any computer can understand. Then, it’s no longer relying on an external file that your printer may not have; it’s simply a mathematical formula that looks exactly the same as you typed it.
How to Convert Fonts to Outlines
Adobe Illustrator:
- Select your text
- Go to Type → Create Outlines
- Save your file
Adobe Photoshop:
- Select your text
- Go to Layer → Smart Objects → Convert to Smart Objects
- Save your file
Important Reminder: Always save a copy of your original file with editable text before outlining in case you want to edit the text later.
Final Checklist Before Submitting Your Artwork
Before sending your design to print, double-check the following:
- The artwork is a vector or high-resolution raster image (300 DPI)
- The design is sized to the final print dimensions
- All images are embedded
- All fonts are converted to outlines
- Colors are set correctly (RGB, CMYK, or Pantone)
- The file format is print-ready
If you keep all this in mind, you can ensure crisp, professional results, prevent unexpected color shifts, avoid delays and extra revision rounds, and reduce setup and production time.