Hofmeyr was born in Cape Town on 20 March 1894.
He was baptised Jan Frederick Hendrik Hofmeyr, but the middle-name Frederick fell into disuse quickly.
Later in his life he would be known to many as "Hoffie", this diminutive form of his surname even being used in cartoons of Hofmeyr published in South African newspapers.

 He was raised by his widowed mother Deborah, a cousin to Christiaan Beyers, after his father Andries Brink Hofmeyr died when Jan was three years old.
Deborah had another son who was five years older than Jan, his brother Andries Beyers Hofmeyr.
Jan also had two half-sisters from his father's previous marriage.
Deborah devoted most of her energies to Jan, and he was the child with whom she had by far the strongest bond.
This strong relationship was probably formed when Jan fell ill with hydrocephaly at age two; he soon recovered and according to the medical wisdom of the day it was felt that he would either become a genius or an idiot.
As it turned out he would be a genius.

Jan was first educated at the illustrious South African College Schools, which he entered in January 1902.
A child prodigy, he progressed rapidly through its grades so that he matriculated four years later in 1906.
He went on to study classics at the University of Cape Town (then still known as the South African College) and in 1909 graduated B.A. with first-class Honours at the age of 15.
At this time he was awarded a Rhodes Scholarship to study at Oxford.
He accepted the award but only made use of it a few years later when he was older.
In the meanwhile he took another B.A. in the sciences in 1910 and an M.A. in classics in 1911, when he was just seventeen years old.
Apart from his studies, Hofmeyr also became active in the university's Debating Society (succeeding Oliver Schreiner as its president), worked as treasurer in its College magazine, and volunteered in its Students' Christian Association.

In 1911, when he was just seventeen, Hofmeyr was commissioned to write a biography of his uncle, "Onze Jan" Hofmeyr.
The project was undertaken with the supervision of former President of the Orange Free State, F. W. Reitz.
The project was completed within a year, the younger Hofmeyr having written it in English and then translated it into Dutch.
Hofmeyr was born in Cape Town on 20 March 1894. He was baptised Jan Frederick Hendrik Hofmeyr, but the middle-name Frederick fell into disuse quickly. Later in his life he would be known to many as "Hoffie", this diminutive form of his surname even being used in cartoons of Hofmeyr published in South African newspapers.
 He was raised by his widowed mother Deborah, a cousin to Christiaan Beyers, after his father Andries Brink Hofmeyr died when Jan was three years old. Deborah had another son who was five years older than Jan, his brother Andries Beyers Hofmeyr. Jan also had two half-sisters from his father's previous marriage. Deborah devoted most of her energies to Jan, and he was the child with whom she had by far the strongest bond. This strong relationship was probably formed when Jan fell ill with hydrocephaly at age two; he soon recovered and according to the medical wisdom of the day it was felt that he would either become a genius or an idiot. As it turned out he would be a genius.
Jan was first educated at the illustrious South African College Schools, which he entered in January 1902. A child prodigy, he progressed rapidly through its grades so that he matriculated four years later in 1906. He went on to study classics at the University of Cape Town (then still known as the South African College) and in 1909 graduated B.A. with first-class Honours at the age of 15. At this time he was awarded a Rhodes Scholarship to study at Oxford. He accepted the award but only made use of it a few years later when he was older. In the meanwhile he took another B.A. in the sciences in 1910 and an M.A. in classics in 1911, when he was just seventeen years old. Apart from his studies, Hofmeyr also became active in the university's Debating Society (succeeding Oliver Schreiner as its president), worked as treasurer in its College magazine, and volunteered in its Students' Christian Association.
In 1911, when he was just seventeen, Hofmeyr was commissioned to write a biography of his uncle, "Onze Jan" Hofmeyr. The project was undertaken with the supervision of former President of the Orange Free State, F. W. Reitz. The project was completed within a year, the younger Hofmeyr having written it in English and then translated it into Dutch.
Jan Hendrik Hofmeyr (1894–1948)