Available Excel APIs

There are several API technologies available for Microsoft Excel. Since they utilize Windows technologies the Excel APIs require a Windows OS.

Important: Sample spreadsheet applications are distributed with the API download for each of the API technologies (RTD Server, ActiveX, DDE). It is important to keep in mind that the sample applications are intended as simple demonstrations of API functionality for third party programmers. They do not have robust error handling functionality and are not intended to be used as production level trading tools.

Recorded webinars providing an introduction to Excel API technologies are available from the IB website at: Recorded Excel API Webinars

Excel API comparison

	RTDServer	DDE	ActiveX
Full API functionality	No	Yes, in API v975***	Yes
Easy to use formulas	Yes	some functionality	No
Use without VBA	Yes	some functionality	No
Designed to not overwhelm Excel	Yes	No	No
Open Source	Yes	No	Yes
Market Data Refresh rate	250 ms	250 ms	1 sec
Sample compatible with 64 bit Excel	Yes*	Yes	Yes**

*available starting with v973.07
**API ActiveX installer is compatible with both 32 and 64 bit applications starting with v973.05
***Starting in API v975, there is a new DDE Socket Bridge API connects to TWS via a socket connection

Limitations of Microsoft Excel APIs

By design, Microsoft Excel gives precedence to the user interface over the data connection to other applications. For that reason, Excel only receives updates when it is in a 'ready' state, and may ignore data sent for instance when a modal dialogue box is displayed to the user, a cell is being edited, or Excel is busy doing other things. A new Excel Real Time Data server (RTD) API has been introduced to help address some of these limitations, but they are inherent to Excel as a trading application and not specific to an API technology.