My keywords are 1st page of search engine while i was opened my Gmail Account.But my keyword ranking position was changed while log out my Gmail Account.Why?
if you want to find the actual keyword position then log out g mail account because if you are sign in then goggle fetches the post you have done with that account.
That's called personalization. Every time you make a search for something while you are log in to your account, Google records that history and use for future search results. The more you search for a certain term and click on the same site over and over again, it somehow gives an impression to Google that you are so fond of the results that you are seeing which leads them to place that certain page on the page 1. What you can do is to clear your history in Google and see what changes happened. It's a pretty natural scenario these days about personalization that affects the accuracy of keyword rankings based on the user's profile, location, etc.
When you are logged in, the SERPs shows you not results based on your historical search data when logged in using your account. And it is the opposite when you are logged out that is why you are seeing different ranking data. Regards, Mark