Which product works the best for cleaning tile grout?

I use the clorox bleach pen. It’s the easiest thing I’ve found that really gets in there.

@gemiwing : YES! Totally the bleach pen. The gel-like stuff really sticks to the grout until it’s clean. It even has a scrubby thing on one end.

I was always told that nothing worked like some soapy water and a toothbrush.

Next time, get brown-ish grout. :D

Chemical:
‘Comet’ is abrasive and works well with ours.

Applicators:
We use a green ‘brillo’ pad with a handle on it and scrub.
I think a toothbrush with Comet (or similar, Ajax) would probably be good too. Toothbrushes are grand for that kind of stuff.

I have some chemical a guy sold me when I lived in Florida, it cost me a fortune, like $40 for a gallon and it is like magic for grout. Flippin’ I have no idea what chemical it is, I have moved with it twice. I have hardly any left. He sold it with no label, because it probably only costs $1 a gallon. Frustrating. The guy worked for my builder. I have no idea where he is now.

A mixture of bleach and washing powder works a treat ;-)

I recently saw a similar question and the person said bleach, but almost daily until it is gone. Applied with a toothbrush.