This is quite a controversial topic.
Today most Khukuri houses make their spines massively thick (9-11mm) to safe time.
Most people say that these spine thickness are strongly exaggerated and not historicaly accurate.
Others say that they in fact were that thick.
I have seen some historical examples of Khukuri, and my impression is that in fact many of those a quite thick. What I've seen is mostly 9mm+ at the base. I've never seen anything under 7mm.
My Theorie (which is based on very little experience) is that there was quite a bit of verity in the thickness, as there was also a lot of verity in Khukuri types which all have different purposes.
There are big heavy chopping instruments that have more similarities with axes than knives (those might reach 1,3mm). On the other hand there are light Khukuris that were intended for martial arts and combat (7mm or less)
This is just a guess. I havent seen enough examples to be able to make any valid statement. This is what seems the most logical to me.
But what do you think?

99% of the time they were being used as a tool, not a weapon. I've used mine for clearing undergrowth, pruning trees, cooking food, scraping hotplates, shaving spear-shafts, dispatching game, butchering meat, splitting wood, tightening screws, levering rocks, and so on. A utilitarian blade needs to be a lot more sturdy than a martial arts blade.

I have three late 19th/ early 20th century khukris and all have very considerably thick spines; 13mm, 12mm, and 8mm. That's quite a bit of variation, but shows that they could be very chunky. As a chopping tool, the heavy weight of the thicker examples is quite handy, they also have much deeper bellies and make fair ad hoc diggers. If I were to use one as a weapon though, the 8mm has significantly more responsive handling.

I personally don't know enough about original Kukries to say if they are overbuilt or not, so I can only judge them as they feel in my hand.

A Cold Steel San Mai Khukuri purchased a long time ago seem robust to me but not ponderous or overbuilt. Same design but different steel.
https://www.coldsteel.com/gurkha-kukri-in-a2-steel-39lmd?returnurl=%2fcoldsteel-knives%2f%3fcount%3d144

A longer than usual Khukuri I purchased a few years ago is fairly heavy, has a thick spine 8.4mm thick at the guard and a bit of distal taper on it's 18" blade 4.5mm near the tip. It does have a lot of blade presence but not too much as I see it more being a short sword rather thanjust a knife. It also isn't a traditional design as it uses a full tang, but the tang tapers from the 8mm at the guard down to 2mm at the end of the handle.

This one described above:
http://www.kultofathena.com/product.asp?item=...7%27+Blade

As a tool or weapon I would feel very well armed for a " Zombie Apocalypse " ...... :lol:


Another one with a much shorter blade is truly much much too heavy in total weight and would put a double bit axe to shame ..... :( :wtf:
Truly monstrously heavy and impractical, but a nice display piece:
https://www.khukurihouseonline.com/5-fuller-chirra-full-flat-tang-kukri-slayer


https://www.khukurihouseonline.com
They do seem to have categories including what they call wall-hangers !

Also interesting but not historically authentic designs, but they also seem to have more traditional one, a careful buyer should decide what they prioritize: Authentic looks and handling or something very different that can be good or bad depending on what one is looking for.

In general terms a thick blade at the guard will handle very differently if it has distal taper than a sharpened crowbar.