Bitmap Images

Best File Format for T-Shirt Printing

The file type of a graphic image can impact the quality of your custom printed t-shirts.

There are two file types: Vector and Raster.

VECTOR	RASTER
Vector files will require specialized graphic software and experience or training to work with the graphic in the graphic program. Most common extensions end with .eps or .ai.	Raster files can be viewed and opened without any issues. Most common extensions (file type identifier) end with .jpg or .png.
A Vector image is the ideal option when you are printing text, logos, or graphic elements that are distinct from other elements (meaning they don't blend together like a rainbow).	A Raster image is a solid choice if the image is a photo or has colors that blend together like a rainbow. In most cases if the image is saved at 12" wide/150 dpi; will likely turn out well.

Check out our side by side comparison of a vector image vs a raster image below.

In the example above; you can see the differences in the clarity and crispness of the text and graphic design. These differences are because of the file format.

Why does the format have such a profound effect? It comes down to the way the graphic image is interpreted during output.Rasterized Images are a dot matrix data structure that represents a generally rectangular grid of pixels (points of color) creating continuous tones. This is why the edges are rounded and the colors in the smiley face are not solid.

Vector Images are defined in 2D points, which are connected by lines and curves to create shapes. Each of these points has a precise position on an x and y-axis. This is why the edges are precise.

Oftentimes, when a designer provides graphic files, they provide raster images. While it's a format that's easily opened and perfect for viewing on a website, it's not good for reproduction in a large size.

*PRO TIP: When you hire a designer to create custom t-shirt graphics for you, ALWAYS request the .eps file (request the file is prepared properly: fonts converted to outlines - no placed images - if they're good they'll know what this means). Save the .eps file in a safe place so anything you choose to print will look crisp and clean.