If Richard is right, here's how I test it:

1) Test your tap water for chlorine...that's your baseline.
2) I bought a glass eyedropper that's marked from .2 ml to 1 ml.
3) Fill an empty 2 liter soda bottle with tap water to the 2 liter level the soda was at.
4) Add .2 ml of the bleach/LC to the soda bottle. Cap and shake a while.
5) Test the soda bottle's chlorine level. Its level minus the chlorine level of the tap water, is the actual strength of your bleach.

If you want to be more accurate, take a 5 gal bucket and add 5 soda bottles of tap water and 1 ml of bleach and test as above. The concentration ratios will be the same but with more water and more bleach the variation is smaller.