BOOMR_lstart :TimeStamp

Time the loader script started fetching boomerang.js (if the asynchronous loader snippet is used).


BOOMR_onload :TimeStamp

Time the window.onload event fired (if using the asynchronous loader snippet).

This timestamp is logged in the case boomerang.js loads after the onload event for browsers that don't support NavigationTiming.


BOOMR_start :TimeStamp

Timestamp the boomerang.js script started executing.

This has to be global so that we don't wait for this entire script to download and execute before measuring the time. We also declare it without var so that we can later delete it. This is the only way that works on Internet Explorer.




Check the value of document.domain and fix it if incorrect.

This function is run at the top of boomerang, and then whenever BOOMR.init is called. If boomerang is running within an IFRAME, this function checks to see if it can access elements in the parent IFRAME. If not, it will fudge around with document.domain until it finds a value that works.

This allows site owners to change the value of document.domain at any point within their page's load process, and we will adapt to it.


Name Type Description
domain string

Domain name as retrieved from page URL

Type Definitions


A Unix Epoch timestamp (milliseconds since 1970) created by

If DOMHighResTimeStamp ( is supported, it is a DOMHighResTimeStamp (with microsecond resolution in the fractional), otherwise, it is


  • number