ExtracText OCR Online is an online service which can help extract text from images like png, jpg, bmp as well as pdf files. If you are looking for a free solution to convert your scanned documents into highly accurate searchable text then look no more!
If you would like to get a better idea of how accurate the service is, you could do so by hovering on any image below and then click on the "ExtracText" button.
Image1 (Some standard text):
Image 2 (A web page with different font sizes and styles):