What makes image search different from text search is that people searching for images are most often looking for some entertainment rather than business-related or informative content.

What else differentiates image search is that image content is often subjective – you can ‘like’ or ‘dislike’ images; besides, more often than not you even don’t know exactly what you are looking for and what you want to find.

So here are some fun free image tools that turn searching for images into fun and also let you find you don’t know what:

Search Images by Color:

Multicolr is Flickr-based color search engines. With it you can mix up to 10 colors and select images matching the chosen color palette.

The more colors you choose, the more colorful images you get in the end:

Each search result has its own URL, so you can share it with friends. Here’s my latest pick:

Search Images by Similarity:

Byo image search will find images similar to the one you upload. The exact algorithm is unclear but it seems it rather focuses on colors, though some similarity in forms and shapes can also be identified.

Retrievr is a Flickr based tool searching for images based on your sketch You can also rate sketches created by others.

Search Images by Theme:

Tiltomo (Flickr based) searched for images by either color palette and texture or theme (too bad those two criteria can’t be combined). It has its own database of Flickr images, which means this database is not always up-to-date.

It is impressive that the engine finds images that really have similar topic (and the similarity is not clear even to a human eye). For example, the following search results definitely have something in common (strawberries) but the similarity is not about shapes, colors or forms, it’s about theme:

Search Images by Face:

Exalead offers imagecontent:Face advanced operator that restricts search results to faces only. Google also provides that feature accessible via advanced search:

Post image by Andyrob