revisions...how many is to much?

i realize that revisions are part of designing, but how many is to much and how do you charge when it becomes excessive? Every once in a while i get a client with the..."let's try this, or "what about this"...till it drives me crazy. revisons are normal, and i usually always oblige, even after it gotten to the point of excessive, but how do you tell them that enough is enough, or how do you stop and tell them that if you want to keep trying different "looks" that it will cost more? what is normal to charge for revisions. thanks for any input

I would negotiate the number of revisions before the sale and then set the price accordingly. If the client wants more revisions, they will have to pay for them subsequently.

Always dig as much info and description as possible before designing.
And let the client know how many revisions they can request.
If you didn't state this, then its your own fault.

I offer two major revisions after the initial concept is agreed upon. And unlimited minor revisions up until the project completion. Minor revisions are simply adding/editing text, slight colour changes or tiny tweaks of the design. Major revisions are adding/editing large volumes of text, altering structures/navigation systems etc.

depends on how thorough you like to be. i like to be very thorough. by default i try to offer 1-3 different concepts with 1-2 variations (including unique page designs) of each depending on how the ideas unfold.

they'll pick a direction, and 3 free revision rounds, after that i'm clear each time i have to wait for feedback, it counts as another round, so they won't say to me "try it in red" and then "try it in blue" after a week of waiting for a response. if they want 5 colour attempts, they need to ask for it all upfront as i can't necessarily charge the week i had to wait for feedback.

if it's for people i have good relationships with (usually people i know personally) i'll consider those minor things favours and don't track them - that's their reward for being on my good side and not making me wait 3 weeks for trivial feedback.