Is Food Color Light Fast?
How to Fade Test

"You dye wool with food color? Oh Honey, it's going to fade!" Really?

A fade test and light fast ratings will help you decide if you should be worried.

By the way, I have read about only two cases of food color severely fading. One was a shawl placed over a sofa in the sunlight and the other was a soaker (that's a diapercover).

Light Fast Ratings by Color

  • Yellow5 = 6
  • Yellow6 = 4
  • Red3 = 3
  • Red40 = 5
  • Blue1 = 5

The highest number a dye can get is an 8. With museum quality shielded lighting the color would remain unchanged for a century.

A 6 means no change for 50 to 100 years while 4 and 5 mean 15 to 50 years.

Red3 would be considered fugitive, it may fade as soon as 2 years.

Before you swear off food color dyeing, here's a few things to consider.

  • This rating system was designed for artists and museums. The artwork would be on daily display under special lighting conditions.
  • The ratings are for the colors alone, not for the colors bonded on wool. No one has studied food color used with wool.
  • Professional acid dyes aren't automatically more light fast. Most of Jacquard's acid dyes are rated 4 to 7. However, hot fuchsia is a 2-3 and turquoise is a 1.
  • The published numbers for professional acid dyes are also for the colors themselves, not for the colors bonded to wool.

Kool-Aid and Wilton Fade Test

The wool scraps in the photo are hank ties left over from other projects. The upper ends were exposed to 4 days in the direct sunlight.

In our test, the light blues and pinks did fade. The dark red faded slightly. But the darkest shades yellow, blue, green and purple still look fine.

Looking at both the scraps and the light fast numbers, we'd suggest two things:

  • Choose yellow5 and red40 if you are worried about fading rather than yellow6 and red3.
  • If you dry your hanks or finished objects outside, keep them in the shade.

How to fade test your own dyed yarn:

  1. Collect
    • yarn snippets dyed with Kool-Aid®, Wilton®, or any food dye
    • clear tape
    • a book
    • a piece of paper (black or purple construction paper is most dramatic)

  2. Lay your snippets across the paper and run a piece of tape down the center.

  3. Place the paper in a book, with half of the paper sticking out in the sun and half hidden in the book.

  4. Leave the book in the sun, a few hours or a few days.

  5. Remove the page and marvel or curse the results.

Products with Yellow5

  • McCormick Yellow, Green and Neons
  • Great Value Yellow
  • Wilton Lemon Yellow, Leaf Green, Kelly and Teal
  • Kool-Aid Lemonade

Products with Red40

  • Wilton No-Taste Red.
  • All red flavors of Kool-Aid
  • Great Value Cherry

More information about red food color.

Hints about blue food color.

Go from Fade Test to Dye Your Yarn Home Page


Enter a word in the box below.

Support DyeYourYarn
Shop at Amazon

Click here to
see how it works.