using windows 8.1 task manager showing firefox 32 bit but mozilla new showing updated

And your question is?

Firefox for Windows from mozilla.org is 32-bit only and will work on both 32 and 64-bit Windows. The current Release is 27.0.1

thanks for your help and i want to use 64 bit if available ?

Firefox is always a 32 bit application on Windows, even on 64 bit Windows versions.

The latest Firefox release is Firefox 27.0.1 (Help > About).

You can find the full version of the current Firefox 27.0.1 release in all languages and for all Operating Systems here:

• http://www.mozilla.org/en-US/firefox/all.html

Mozilla does not have any Win64 builds of Firefox currently other then on the unstable Nightly development channel for breakage/regression monitoring purposes.

Win64 builds still have a number of hurdles to deal with before they are stable for Release and since the 32-bit builds work fine there is not a priority to have 64-bit Release builds for Windows.