what is optimum length for html title tag in Unicode format
I have a website that generates its title tag dynamically. the title tag is in unicode format.
the title tag is limited to 65 character but sometimes Google doesn't show title tag completely in SERP. 
I'd like to know what is the optimum length of title tag in terms of seo for unicode titles, and is there any difference between Unicode title and non-Unicode title tag?
And what about other search engines Bing, Yahoo and so on.
what is optimum length for html title tag in Unicode format
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I have a website that generates its title tag dynamically. the title tag is in unicode format.
the title tag is limited to 65 character but sometimes Google doesn't show title tag completely in SERP. 
I'd like to know what is the optimum length of title tag in terms of seo for unicode titles, and is there any difference between Unicode title and non-Unicode title tag?
And what about other search engines Bing, Yahoo and so on.