Here you can find a basic, open source web based script to decode FIX messages. Now, you may be wondering, what exactly is a fix message.
In short, a FIX message represents a sequence of fields whose values are associated with unique numbers (tags). This method of communication is commonly used by brokerage firms and banks wishing to trade financial instruments on various stock exchanges of the world.
For further information, click here.
The inspiration of this tool was the observation of people opening up large pdf files and scroll back and forth in them to decipher these messages.
Disclaimer: The process takes place entirely within the browser. None of your FIX data is sent to the server. It was designed for a standard FIX 4.2/4.4 interpretation. Some exchanges e.g. EURONEXT use many custom non-standard tags.