James Watt was born in Greenock, Renfrewshire, Scotland, to Agnes Muirhead and James Watt Sr. His father was a shipwright, ship owner, and contractor, while his mother came from a distinguished family.

Watt was often unwell as a child and received much of his early education at home from his mother. This allowed him to pursue his own interests and learn at his own pace, developing a strong foundation in reading, writing, and arithmetic.

Watt later attended Greenock Grammar School, where he showed a particular aptitude for mathematics, science, and practical skills. He excelled in these areas, surpassing many of his peers. He demonstrated natural mechanical abilities building models and tinkering.

Watt began an apprenticeship with his mother's cousin, a mathematical instrument maker in Glasgow. This exposure furthered his skills in precision work and design.

Watt then travelled to London to train as an instrument maker. However, his health suffered, and he was only able to complete a year of his apprenticeship.

Despite not completing his full apprenticeship, Watt secured a position as the instrument maker at the University of Glasgow. This provided him with access to resources, academics, and an environment conducive to learning and experimentation.