This is a free E-ink image converter. E-ink screens such as used on most ebook readers (e-readers) are limited in that they (with a few exceptions) are only supporting gray scale images and no colors. But they are also very limited in how many different gray scale values they can represent. Most support 16 gray levels and some even fewer. This leads to so called banding in images displayed on these screens, which looks quite bad. This converter uses a dithering technique to limit the banding in the converted images.
If the image conversion tools available here are not enough, you can do pre-conversion steps on the image prior to converting it here.
Many E-ink devices lets you pick an image to show on the device when it is switched off. For instance, to always show an image on an Onyx E-ink device, simply save the converted image (by long-tapping it), find the downloaded image in the device storage and long-tap the image to get a menu where you can choose "Set as shutdown image". Please search the Internet to figure out how to do it on your specific device.
This converter is free to use. I cannot be held responsible for any use or misuse of this tool.
Feel free to send feedback and questions to email@example.com.