Is No. 13 considered lucky or unlucky

there is no logical explanation on that. it's just a number.

Numerologists consider the number 13 unlucky. If peole consider on baseless grounds as no. 13 as unlucky or lucky for them then its rubbish. Moreover numbers dont have any relation with luck, atleast thats what I believe.

i dont think it depends on each people...

I was born on 13th September...cannot say if it is bad for me or whether I am lucky or unlucky.

In West ,13 ;especially 13 The Friday is considered unlucky. I do not know why . In india there is not so much of Negativity with 13 . However ,In Panchkula,a city in Haryana surrounding Chandigarh ;there is no Sector-13 . Instead the Sector after 12 is named as 12-A;which I find odd as most of the cities in India have Sectors,Houses etc of this Number. There are however no Houses with Numbers 420 at most of the places since 420 is considered the Number associated with a Thief. (420 Numberi) . And 666 is also avoided as that is considered the Number of Devil in West (and probably Shaitan in India) .

I wouldn't say that number 13 is lucky nor unlucky. The belief actually depends on the person. As far as I know, most gamblers believe that 13 is such an unlucky number. They refrain from gambling every thirteenth of the month. Most buildings don't have thirteenth floor. And some people would say to be extra careful during a Friday the thirteenth. I actually couldn't see any relevance or justification for believing such things. But since we have such freedom, it's up to the people on what to believe about the number 13. In my part, I don't really believe in misfortunes. What I believe is that hard work would eventually lead to success or fortune but never misfortune.