1. In a digital medium environment to determine which fonts are similar to rendered text in an image, a method implemented by one or more computing devices comprising: obtaining a model, by the one or more computing devices, that is trained using machine learning that is applied to a plurality of training images that include: an anchor image having text using a font type; a positive image having: text that is different than the text of the anchor image; or text having one or more applied perturbations; and a negative image having text that is not in the font type; determining similarity, by the one or more computing devices, of a font used for text in an image to respective ones of a plurality of fonts using the obtained model; and controlling output of a result of the determined similarity in a user interface by the one or more computing devices.