The micro button is one of a standard web button size 80 by 15 pixels. You may see some websites use micro button to promote their websites or their affiliate websites.
If you want to create this micro button for your website or blog, there’s an online tool called “Brilliant Button Maker” this tool will help you easily generate a 80*15 micro button using their tool. The tool is easy to use, you can choose font, color for text and background, change text for your button, you can also use two images (one on the left and the other on the right side) to decorate the button.
Link : Brilliant Button Maker