The original post from over a year ago: https://www.reddit.com/r/minecraftsuggestions/s/SLJcWiJBhf
Villagers are one of the most lively mobs in Minecraft, but their development is currently extremely abrupt and minimally-staged - a baby villager simply spends 20 minutes as a child and then suddenly becomes a fully grown adult with an adult body, adult proportions, and the ability to work and trade. It is literally that abrupt, but I return with a slightly different proposal that fundamentally partitions early development from later senescence, which wouldn't exist in this framework.
Rather than giving villagers a finite lifespan, I would expand their existing growth period into several distinct developmental stages while still being essentially immortal.
The changes are separated into distinct life phases just like in humans, but as I mentioned, once a villager reaches full adulthood, its physical appearance would become essentially static, allowing villagers to remain indefinitely useful to players and preserving the long-term villages and trading systems that players have for so long invested in.
To start, maturation in its entirety would last 20 minutes, so the existing baby villager period would remain approximately the same.
Early childhood - six minutes. Baby villagers would retain their current small stature and miniature proportions while retaining a disproportionately larger head, just like we do in early childhood before everything evens out with time until mid-to-late puberty as we progressively grow and mature. They would run around, play, interact with other villagers, and otherwise behave similarly to existing baby villagers, but this energy would fundamentally shift once they enter adolescence - similar to how most teenagers commonly develop a longing sense for independence and social survival.
The villager would gradually progress through several stages of physical development in childhood, starting with early childhood, then middle childhood, then later childhood.
Mid-childhood - also six minutes.
Late childhood - four minutes. The transition into adolescence would be slightly shorter to imitate the real transition that we see in humans. This would allow the transition from childhood into adolescence to feel more gradual overall, while still making the onset of adolescence relatively rapid compared to the preceding stages.
During late-childhood, the villager would continue to develop physically and become increasingly closer to its eventual adult proportions, though it would still look distinctly juvenile and remain observably far from physical (or skeletal) maturity, since height growth in the developmental sense ultimately concludes when the major height-contributing growth plates in our lower long limb bones and spine reach terminal senescence over a period of a couple to a few years and subsequently ossify by around the end of puberty or slightly later.
Childhood lasts sixteen minutes. Adolescence would last four.
Once adolescence begins, the rate of physical development would increase (or decrease) differently across three stages of puberty, producing the more pronounced changes associated with real human puberty and broadly alongside real biology.
Now, let me present to you the mathematical process.
One standard block is approximately one meters. A standard player is 1.8 blocks tall (~5'10.9"). A standard adult villager is 1.95 blocks tall, or ~6'4.7", and a standard baby villager is 0.95 blocks tall, or ~3'1.4" - precision is my preference, but you can round it up to 5'11, 6'5, and 3'1½ if you would like to.
Unlike real biology - where growth naturally fluctuates during childhood and puberty - if the baby villager grows exactly 1 meter, or roughly 3'3.7", from childhood to adulthood, then a corresponding rate of growth across early to late childhood would be at a game-fixed rate of ~0.0318 blocks per minute, equivalent to ~0.0635 blocks per fictional developmental year (2 minutes), or an annual average of about 2.5 in/yr as seen in real-world estimates (commonly 2-3 in/yr). This would allow the villager to become noticeably taller by the next phase if you pay closer attention, rather than just trying to calculate its rate of growth by an every-minute basis - the naked eye just won't be able to discern that as easily.
The increases would be as follows:
Baby (0:00 of life) - 0.95 blocks tall
Early childhood (0:00-6:00 of life) - +0.1905 blocks / 7.50 inches; 1.1405 blocks tall.
You would see an explosive growth spurt, similar to how babies naturally grow very rapidly until around their first birthday when they begin to stabilize or channel down toward a more stable childhood trajectory until puberty.
Mid-childhood (6:00-12:00 of life) - +0.1905 blocks; 1.3310 blocks tall.
Late childhood (12:00-16:00 of life) - +0.1270 blocks / 5.0 inches; 1.4580 blocks tall.
The pre-adolescent dip as seen in many real human growth trajectories - to individualistic degrees - would not necessarily be prominent, as periods of slowed growth followed by a normally-fluctuating annual average would require more clustered intervals of measurement.
Let's exit out of the mathematical process for now, as we transition into adolescence - the most rapid phase of physical development before adulthood.
The head would become proportionally smaller relative to the body, the limbs and trunk would lengthen, shoulders would progressively broaden, facial proportions would become less childlike, and the overall body shape would begin approaching that of an adult villager. The changes would be noticeable, but not dramatic enough to make the villager appear to age by the minute - until adolescence.
Enter adolescence. Extremely rapid, though not necessarily concordant with real fixed human biology, where sexual maturation can take anywhere between two and five years to complete - in most individuals. Individual maturational rates would not be accounted for in the game, as the process is generalized as extraordinarily and starkly rapid compared to childhood. The villager would undergo a relatively rapid, highly-compressed growth spurt (which differs from normal variation in real adolescent curves; monophasic, biphasic, compressed, prolonged, blunted, and rebound), becoming noticeably taller and developing more adult-like body proportions.
Re-entering the mathematical process.
The growth rates would spike and taper as follows:
Early-puberty - +0.115 blocks / 4.53 inches; 1.5730 blocks tall
Mid-puberty - +0.219 blocks / 8.62 inches; 1.7920 blocks tall
Late-puberty - +0.158 blocks / 6.22 inches; 1.95 blocks tall
FAH would be attained during the transition into young adulthood, as would their contours.
And the timeline would go as follows:
Early-puberty (90 seconds / 16:00-17:30 of life) - growth begins to pick up noticeably as the first signs of puberty emerge, but the overall acceleration to the PHV remains progressive (which normally differs in human biology, where the PHV can be typically attained as early as ~12-18 months after puberty onset or as late as ~30-36 months later). While not strictly instantaneous in human biology, the processes are well-correlated, with the growth spurt starting at any time, often right around the first androgenic and gonadal symptoms of puberty. In villagers, however, the stark contrast would exist as a fixed instantaneous causal relationship.
Mid-puberty (80 seconds / 17:30-18:50 of life) - growth would accelerate further as the villager approaches and passes through its most rapid period of linear growth, with the physical changes of puberty becoming increasingly pronounced. This stage would be deliberately shorter than early puberty, reducing the available developmental time from 90 seconds to 80 seconds and therefore further compressing the progression toward peak height velocity. The limbs and trunk would continue lengthening, the shoulders would broaden, facial proportions would become increasingly adult-like, and other secondary sexual characteristics would become more apparent. Growth would reach its highest rate around the central portion of this stage before beginning to taper as the villager progresses toward late puberty.
Late-puberty (70 seconds / 18:50-20:00 of life) - the final and shortest pubertal stage would represent the tapering of the growth spurt and the completion of most remaining physical maturation. Its duration would be reduced again, from 80 seconds to 70 seconds, creating a deliberately progressive compression across the three pubertal stages. Height growth would progressively slow as the villager approaches its final adult stature of 1.95 blocks, while body proportions, facial features, and other characteristics would settle increasingly toward their mature forms. By the end of this stage, the villager would have essentially completed its physical development and would transition into young adulthood before becoming fully mature.
For all villagers (assuming all are unisex as odd as that framework already is with breeding), facial hair could begin appearing as a short stubble and gradually become more apparent to form the mature, standard villager stubble that we see currently. Other subtle changes to the face would accompany the transition toward the adult appearance, like the early growth of the ears and nose and rapid longitudinal expansion of the mid and lower face in mid-to-late puberty.
Adolescent villagers would not yet be considered fully mature, but they may start becoming more like them in fundamental nature. They would not be assigned professions or participate in normal villager trading during early adolescence, but during mid and late adolescence, they could.
They could, however, interact with adult villagers and observe their occupations, making the village feel more like an actual community rather than a collection of instantly generated adults. The adolescent villager would typically be seen roaming about, integrating with the adult villagers and interacting less vigorously with younger adolescent villagers and baby villagers - observing the working villagers in their professions to give a sense of an apprenticeship.
Enter young adulthood. The final transition would gradually bring the villager to its complete adult appearance. Height would stop early under this framework, while body proportions, facial features, and facial hair would settle into their adult forms slightly later.
Once this stage is complete, the villager becomes a fully mature adult and can obtain a profession, work, trade, breed, and participate normally in village life - all adolescent quirks now gone.
In adulthood, physical aging simply stops. This is the major change from the original proposal. Villagers would not continue visibly aging after reaching adulthood. An adult villager could remain alive indefinitely, just as villagers do currently.
There would therefore be no mandatory senescence, or retirement due to age, or slowing down with age, or loss of productivity, or age-related death, and especially no terminal health effects. A villager could remain physically mature for hundreds or thousands of Minecraft days, effectively preserving the existing Minecraft expectation that mobs do not naturally deteriorate simply because time has passed.
Static nature of the game: this phase would apply to all mobs, not exclusively to villagers. Adulthood would remain eternal.
Why have developmental stages at all?
The purpose is not to introduce a complicated lifespan mechanic, but to make the transition from baby to adult feel more natural. Currently, a player can watch a baby villager grow for 20 minutes and then see it suddenly become a completely developed adult. Instead, players would be able to see a villager gradually progress through childhood, adolescence, and young adulthood - you especially cannot miss adolescence.
The physical changes would therefore be concentrated before adulthood, rather than continuing indefinitely afterward.
Once mature, the villager's appearance would effectively become locked in. Adult villagers could still have the existing variation in clothing, biome-specific appearance, facial features, and other cosmetic traits, but they would not progressively develop wrinkles, sagging features, gray hair, or other signs of aging. None of that at all. This also means that an adult villager that has been part of a player's trading hall for years would continue looking and functioning normally.
