What is a white underbase
Updated May 20, 2026
Why white underbase is used and when it applies
A white underbase is a layer of white ink printed underneath a design to help colors appear vibrant, accurate, and visible, especially on dark or colored garments.
Because inks are partially transparent (e.g., DTG), the color of the garment underneath can affect how the final design looks. A white underbase acts as a neutral foundation so the colors printed on top appear closer to their intended shade.
Note: A white underbase does not alter your design colors.
Why a white underbase is needed
When printing directly onto dark or colored fabrics, inks can appear muted or distorted if printed without a white layer underneath.
For example:
- Blue ink printed directly on a yellow shirt may appear greenish
- Bright colors printed on black garments can look dull or washed out
A white underbase prevents the garment color from showing through and altering the design's appearance. This ensures colors look bold and consistent across different fabric colors.
When a white underbase is used
A white underbase is applied automatically when a design meets certain conditions, including when the design is:
- Colorful and printed on a dark or colored garment
- White or includes white elements
- Completely black and printed on a black or very dark gray garment, which helps preserve fine details and texture
DTG Printing Note: For DTG products, a white underbase is printed first, with colors printed on top. This helps colors appear vibrant, and details stay visible on dark garments.
In many designs, the white underbase may cover most or all of the print area, even if white is not visible in the final design.
How white underbase affects real prints
Let's say you upload a colorful logo and place it on a white shirt and a black hoodie.
- On the white t-shirt, your design prints directly onto the fabric, since the garment itself already acts as a light base.
- On the black hoodie, Fourthwall automatically adds a white underbase layer beneath your design. This prevents the black fabric from dulling or distorting the colors.
As a result, your design looks consistent and vibrant on both products, without you needing to change anything. Importantly:
- Your artwork itself is not modified
- The white underbase is typically not visible in the final print, though it may appear on the edges of very small or pixelated details on dark garments
- You are not charged extra for the underbase
When the underbase can be visible
On DTG prints on dark garments, the white underbase can occasionally show along the edges of very small or pixelated design details. This happens where the color ink layer is thin or doesn't fully cover the underbase, exposing a hint of white at the edge.
To reduce the chance of this happening:
- Upload artwork at a high resolution so fine details print cleanly
- Avoid heavily pixelated or low-resolution elements in your design
- Order a sample to check how small details print on dark garments before launching
Note: While a white underbase significantly improves color vibrancy on dark garments, colors may still appear slightly less bright than on light-colored fabrics due to the fabric's texture and DTG printing. This is normal and helps ensure consistent, high-quality results across different garment colors.