How to change DPI online
Dots per inch (DPI, or dpi) is a measure of spatial printing or video dot density, in particular the number of individual dots that can be placed in a line within the span of 1 inch (2.54 cm). Many resources, including the Android developer guide, will use the term DPI interchangeably with PPI, however.
We will be using the online resource tool which can be found at www.online-convert.com.
Navigate to the website www.online-convert.com.
Scroll down to image converter and enter the desired file format. If you do not wish to change the format, simply choose the format which the existing file is in.
Upload your image using the Browse button or use an online image by inputting the URL.
Select any enhancements you wish to perform on your image (optional). Then scroll down to the field labelled as "DPI" and enter the desired value. Finally, click on "Convert Image".