Unfortunately, the opportunity to find a twin online quite a bit. Often there are services that supposedly have a voluminous database of photos of celebrities and ordinary people, taken from social networks and search engines. However, these sites provide lookup services on a fee basis, and payment is made by sending an SMS to a specified number. Such resources are best avoided as most often, they are fraudulent and do not perform the search, trying to cash in on unwary visitors.
One of the few truly free service that helps to find double online, is Play-analogia. Here you need to register and upload your photo. It is desirable that it was good quality, and the image was located in front. Special markers mark the location of the eyes in the photo below, the search results were more accurate, and then click "search". The service allows you to search for free double only three times, after which the service will be provided on a paid basis.
Find twins allow a variety of mini-applications in social networks, for example, "Vkontakte". If you are registered in this social network, look for the app "Doubles" or similar. These services perform a lookup in the database of pictures of celebrities or user is already registered in the application. In the latter case, you will be able to find not only double, but also to get a link to his page in the social network.
Try to use the services of the Internet search engines that allow finding similar images. For example, similar services are provided by Yandex or Google. Upload your picture and follow the procedure search. This method does not always work, but if you're lucky, among the results you will see pictures similar to you, including celebrities. Found photos, you can easily save to your computer.