Allows you to search for images on the Web using keywords or uploaded images. From the results page, click on Tools and then click on Usage Rights. This will allow you to filter results based on permitted usage.
The Metropolitan Museum of Art has made over 400,000 images from its collections available for free online. Users can search, browse, share, and download the images with no copyright restrictions.
Using images ethically
Finding images that you are permitted to use for your work is actually pretty easy. Many photographers and artists make their images available under a Creative Commons license and allow them to be used freely. There are different kinds of Creative Commons licenses, so remember:
Make sure that the image is licensed for the type of use you intend
Always give attribution, even if the image is in the public doman (a slide at the end of a presentation or an entry in the References list of a written work is usually sufficient)
For more information on what the different usage rights designations mean, consult the link below: