Skip to content
FREE Shipping On All Domestic Orders $50+
FREE Shipping On All Domestic Orders $50+
How To Test Color Fastness

How To Test Color Fastness

1. Ideally, you should always pre-wash your sewing fabrics. Not just to test for their color fastness but also to pre-shrink.
If pre-washing fabric is not possible, here is how you can still check for colorfastness.
2. CUT SCRAPSCut small pieces of your fabric and sew them onto a piece of white fabric roughly double in size.
Make sure your white fabric is cotton or another natural fiber such as linen. Polyester doesn’t absorb dye so you won’t get accurate results when doing a color fastness test.
3.Fold the white fabric in half so the colored fabrics are sandwiched in the middle.
Wet the fabrics thoroughly the way you wish to wash your final sewn item. This may be in hot water or cold water and with or without soap. Generally hot water with soap results in the greatest color transfer.
4. CHECK THE RESULTS Check whether the white fabric has any dye transferred on to it.
You can see from my test that the darker denim and the red run while the chambray and light blue do not. I would not put a white cotton lace on the denim or red since it would probably have some dye transfer..
5 COLOR FASTNESS - PROBLEM SOLVING If the colored fabric is running, then you could try washing it in a salt wash to set the dyes better. A small amount of white vinegar can also be tested. Test a small scrap for color fastness before you dunk your whole fabric into either salt or vinegar.
There are also commercial products available to stop dye running.
However, if you still find the color is bleeding even after washing the fabric, you might just be better using it for another project without contrasting colors.
Previous article How to transfer a photo onto fabric.
Next article How can I make fabric more interesting?