For every in-stream picture, an image link is created which takes up the Twitter character space.You simply need to maintain the 2:1 ratio of the images which can be reduced to a smaller version to effectively fit your follower’s stream.
Your Twitter profile picture is your main identification mark that will be visible to everyone.
It will be visible on your home page, on the Twitter stream of your followers whenever you Tweet and so on.
Since it represents you or your brand, the image should be of the highest quality.
Header Photo: 1500 x 500 pixels (a maximum 10 MB file size) You can use an eye-catchy, creative image for your high-resolution header photo on your Twitter profile page.
But, with so many social media platforms, how do you remember the various image size optimisation guidelines?