I wear a size 7. I saw others say it runs 1/2 size smaller the suggested size on amazon says 10. Should i buy a 8 or 8.5 or 10?

I actually wear a 6.5 in regular flat shoes but I buy 7.5 in Brooks. Some brooks have a narrow toe box and with socks this works for me.

I may need z 12.5. If i convert to a mens size for length should i order mens narrow to get a womens medium width equivalent?

Keep in mind, there is a 1 ½ size difference in length between men’s and women’s shoe sizes. Men shoes are usually wider than women’s. Therefore, when you convert women’s shoe size to men’s, subtract 1 ½ from your US women’s normal shoe size and the width differences. For example, if you are a women’s size 9 ½ wide, then your men’s shoe size would be an 8 medium. I hope this helps.