what is the maximum size of the keyword we can use in the site? ex: i love playing free online games like action games arcade games ? i mean how many words max. i can use in keyword ?
As far as I know there is no technical limit on the tag, but, the keywords placed in that tag should reflect the content of the page they are on. If the keywords placed in your keywords tag aren't used on the page there is no reason to have them in the tag. keyword tags are largely ignored by the search engines but if you decide to use the keyword tag keep it focused on the page content, not the entire scope of the site.
There is no hard and fast rule regarding the length of key phrases but from search engines point of view and according to guidelines, it should be about 256 characters.
There is no limit. There are only two types of keywords : the short tail keywords and the long tail keywords. Short tail keywords are those broad keyword that you can use : Example: saigel.com, saigel.com online games, action games, arcade games, etc Long tail keywords are those that are more specific than the short tail keywords. Example: play saigel.com online games, action games at saigel.com, siagel.com arcade games, etc. If you have a very short keyword then the competition might be too hard for you to compete in, so targeting a medium tail keyword would do. Long tail keywords are used mostly for conversions because when people search for something specific, they usually type in SE box the exact word they are searching for.
It is should be not so long as many sites of back link creation consider it spam when keyword length is more than its prescribed format.