Is there any way to tell how old a snake may be?
Without having the actual hatch date, not really.
Just like humans, animals have a varied adult weight and length/height range. There are average values associated to this, where the majority of the population will fall. Then there are the extremes where smaller than and larger than average individuals will fall within the scope of the given size (we'll just lump weight, length, height into "size") range for the species.
The above assumes ideal conditions for optimized size potential. For the sake of argument and simplicity here, most/all reptiles have indeterminate growth - they keep growing to some extent after their body says, "hey, you've reached adult size." This is how you can potentially get record size animals.
From here, things get complicated. Length/height are dually tied to 2 predominant life factors: 1) genetics and 2) environmental influences. Statistically, averages will still factor in within genetics, but if your parents are both long/tall, then the likelihood of you also being long/tall are pretty high. That said, my father is almost 5ft 10in. His older sister is 5ft 11in, youngest sister is 5ft 7in, little brother was 6ft 2 or 3in, and I'm not sure on my grandparents on that side. On my mom's side, my great grandfather was 5ft 7in, great grandmother was 4ft 11in, grandfather was 5ft 6in, grandmother 5ft 2 or 3in, mother is 5ft 2 or 3in, uncle is 5ft 8in, and I roll in at 5ft 6in - I'm not even as tall as my dad! My mom says I got the "short s**t Italian genes", which is her side of the family.
Going off of this and moving from genetics, there are then environmental influences. These can be food (nutrition), stresses such as trauma, and other factors. Back when farming was the predominant livelihood in the US, typically your tallest people were usually your "corn fed" country folk. Food and good nutrition was immediately available. In contrast, back then city folk were usually shorter due to lack of nutrition. Fast forward to present day, and even with all the junk food out there, the average US male and female height has increased due in part of readily available good, nutritious food throughout the entire year. In regards to myself, I ran on the high school cross country team all 4 years. To be a distance runner, one has to be mindful of good nutrition in order to have the needed fuel for both practices and races. Even with me eating fairly well (my family wasn't nuts when it came to health food, but we didn't eat horribly either, mom usually always cooked dinner each night), getting pretty decent nutrition, my genetics and that nutrition combined said NO! You will only be 5ft 6in.

oke: :awcrap:
In comparison, I have 2 friends that played sports and ate well, one with parents of average height and one with parents that a taller than average. My friend from average parents graduated high school at 5ft 4in, he's a year younger than I and he's now 6ft. My best friend, who also ran cross country with me and whose parents are taller than average, is also 6ft and his little brother is 6ft 5in. High school for all of us was 16 years ago.
Long explanation summed up, there's no way of knowing how old a snake is visually unless you know the actual hatch date. Food intake, whether proper or not, as well as genetics all factor into how long a snake is or isn't. Each one grows at different rates.
140 characters are for wimps
Oh and....
https://ourworldindata.org/human-height/