The current Firefox Releases works on Windows 7, 8, 8.1, 10, 11 https://www.mozilla.org/firefox/113.0.2/system-requirements/

Note while no version has been set currently, however Windows 7, 8, 8.1 may not be supported after Firefox 115.0 Release (next Release the ESR will be based on). [Open Bug 1594270 (win7-eol) meta] Remove support for Windows 7

At this point you will have to use Firefox 115.0 ESR, or to use more current Firefox Releases to update to Windows 10 or 11 or perhaps use a Linux distro.

The current Firefox Releases works on Windows 7, 8, 8.1, 10, 11 https://www.mozilla.org/firefox/113.0.2/system-requirements/

But is the current Firefox the best version for using with my OS and older CPU and limited RAM or would an earlier version of Firefox be better?

You may need to choose 32-bit Firefox is you want a smaller memory footprint. You can select between 32-bit and 64-bit on this download page:

https://www.mozilla.org/en-US/firefox/all/#product-desktop-release

Older versions of Firefox that aren't offered on that page are no longer supported. They are available, but not recommended because Mozilla discloses the fixed security vulnerabilities after each major update.

See also: Install an older version of Firefox

You may need to choose 32-bit Firefox is you want a smaller memory footprint.

Tech specs on my laptop: - Intel Celeron N2830 @ 2.16 GHz - 4 GB RAM - Windows 8.1 with Bing (64-bit)

I would hit ebay and buy a better laptop. With these current specs you'll come back here in time complaining like soooo many other users that Firefox using up all the resources.

jscher2000 - Support Volunteer said

You may need to choose 32-bit Firefox is you want a smaller memory footprint.

Do I need older versions to speed my computer up?

Unless someone has conducted a careful experiment with your OS, RAM usage pattern, hard disk capacity/fragmentation, that would be idle speculation.

With these current specs

With so little physical memory you need to be cautious what applications are running and especially avoid running other applications when you use Firefox, as as soon as Windows start to use the page file browsing can become very hard.

so little physical memory

When I got my first desktop in 2005, it only had 512MB of RAM. What's normal today?

as soon as Windows start to use the page file

You are running a 64-bit OS and that means that memory gets allocated in 64-bit chunks and thus uses twice as much memory compared with a 32-bit OS or 32-bit application, so 8 GB memory is usually recommended for running 64-bit applications on a 64-bit OS. You can add extra virtual memory via a page file on the hard drive, but that is always much slower.

I'm not in a position to buy a new laptop, are those specs really that bad for using current programs?

Celeron is Intel’s branding for their bottom-tier line-up of CPUs meant to be used with undemanding workloads.

i9 i7 i5 i3 Pentium Celeron

The Intel Celeron N2830 is old as it was released Q1 2014. https://www.intel.ca/content/www/ca/en/products/sku/81071/intel-celeron-processor-n2830-1m-cache-up-to-2-41-ghz/specifications.html

The most RAM you can use with this CPU is 8GB of DDR3L 1333 at 2 channels according to ARK.