There is a transcription extension to be used in Google Chrome in order to transcript a webpage written in the Persian script into Alefbā-ye 2om. The extension can be added here.
The underlying transcription tool is also available here. Entering a Persian text into the active window results in the transcription of the text into Alefbā-ye 2om. If a word has multiple matches, you can make another selection by clicking on the word.