What is resolution? What resolution should my artwork be for uploading?

Resolution refers to the number of dots per inch (dpi), or the amount of detail the image has. Higher resolution means a more detailed image, and also larger file and longer upload time. For best results with most products, save your artwork to 300 dpi (dots per inch) at the final print dimensions (full bleed size when uploading an entire product design). T-Shirt images should be saved to at least 175 dpi at 100% of the dimensions at which they will print to ensure high quality printing results. Your images will be sized proportionally based on shirt size (default size is large). Bleed size does not apply to T-Shirts as the full bleed and the trim size are identical. Simply increasing the DPI setting in a graphic program does not improve the resolution.