As other answers have stated, we do not know enough of the entire history to pinpoint exactly how old Konoha is, but we do know some time frames to narrow it down. It would appear Konoha is younger than it appears, and I would say Konoha is no more than 80 years old in Shippūden and barely 100 years old in the Boruto series.
These timelines are not 100% accurate due to guesstimating, but they’re pretty close in regards to the entire timeline as a whole and all 3 points of view line up to support each other.
Hashirama and Tsunade
Hashirama died during the First Shinobi War, which occurred not long after the founding of Konoha
The war started not long after the system of one shinobi village per country was established by the founding of Konohagakure after the Warring States Period.
At some point, Hashirama came to bind most of the tailed beasts and sold them to other villages during the First Shinobi World War, to promote peace and tranquility ... However, this peace was short-lived. Hashirama died during the war shortly after the village began to flourish, and the mantle of Hokage was passed onto his brother, Tobirama Senju, who became the Second Hokage
Ok, we have a start. All it says is "not long", so I would put this time period no more than a few years. During the period of the Warring Ages and the First Shinobi War, as shown in Chapter 619, Hashirama was alive when Tsunade was very little. I would say she is roughly 6 years old at this point.
At this point, Konoha is ~10 years old.
Next comes the Second Shinobi World War, taking place 20 years after the First Shinobi World War ended.
Even then, the peace only lasted another twenty years until the Second Shinobi World War erupted.
Based on the First War's wiki, the final moments of the war mimicked the actual World War I, which leads me to assume the First Shinobi War lasted 4 years.
The conclusion of the First Shinobi World War mirrors the events that followed the real-life First World War. World War I was ended with armistice, before a treaty was finally signed. ... Nevertheless, within twenty years after the signing of the treaty, World War II would begin.
If we account for that timeframe, this puts Tsunade at ~30 years old during the events of the Second Shinobi War.
At this point, Konoha is ~34 years old.
We do not know much about the events between the Second Shinobi War and Third Shinobi Wars, but if we skip ahead the beginning of the series, Tsunade is stated to be 51 years old; 55 in Shippūden. This is roughly a ~25 year time skip
At this point, Konoha is ~59 years old.
The Sarutobi clan was one of the first clans to settle in the newly founded Konoha, to which Hiruzen was one of the first generations to come it and even be trained by the First Hokage himself.
The Sarutobi clan was one of the first clans to settle in the newly-created Konohagakure
Hiruzen was part of the first generation of ninja produced by Konoha
Hiruzen early on displayed prodigious talent in the ninja arts, earning him additional training from Hashirama Senju, the First Hokage
This means Hiruzen was alive, but young during the founding of Konoha. Using the same deduction as earlier, Konoha is ~10 years old at the start of the First Shinobi World War and during this war, Hiruzen is appointed to be the 3rd Hokage by the 2nd Hokage.
Tobirama volunteered himself instead, and before going to his death he appointed Hiruzen as Third Hokage
Furthermore, based on his wiki, Hiruzen was 68 years of age at the start of the series, which is 17 years older than Tsunade at the start of the series. Based on the guessimated age of Tsudande from the above, Hiruzen is only 23 years old during the First Shinobi World War, which (again) starts not very long after the found of Konoha.
At the time of Hiruzen's death, it is stated that he is 69 years of age, which leads to the assumption that he maintained a life of 46 years after being appointed as the 3rd Hokage.
If we add the starting ~10 year span at the beginning, Konoha is ~56 years old.
Kakuzu is the oldest known shinobi who age is known at a whopping 91.
Age - Part II: 91
Trivia: Kakuzu is the oldest shinobi whose age is known.
Kakuzu originated from the village Takigakure, and during the founding of the villages, he was sent to assassinate Hashirama.
Around the time of the village's formation, the village tasked Kakuzu with assassinating Hashirama Senju, the First Hokage
Given how Hashirama was a high valued target, it’s likely Takigakure sent somebody they could count on; somebody older and more experienced. I guess Kakuzu was 20 - 40 years old. Since Kakuzu was killed at the age of 91, and having fought Hashirama around the time of the villages’s founding,
This puts the timeframe of Kakuzu’s battle with Hashirama and Kakuzus death anywhere between 50 - 70 years.