Google Cultural Institute's feature means that online visitors can explore the building on Streetview and see of in-depth details that are usually too far away in the high ceilings to be seen with the naked eye.
The access is significant because, for more than 1,000 years, the three domes in London's famous Cathedral were thought to show beasts, birds and fish as God created them - however, new technology appears to suggest the images portray something different.
St Paul's:
Architect: Sir Christopher Wren
Built: 1675–1720
Tower height: 221ft / 67m
The images, painted by William Blake Richmond in 1890, could appear to depict the theory of evolution.
Internet giant Google has been detailing every inch of the building using high-resolution cameras that have, for the first time, shown the 30 metre-high ceiling in great detail.
The cathedral's head of collections, Simon Carter, told The Times newspaper that the mosaic appears to support Darwin's theories about the survival of the fittest - which he said is shown through a depiction of a fish with teeth "fighting for survival."
From the ground and looking up at the ceiling, Simon Carter, said that the fish image appeared to be a "calm mill pond."
He added that when seen on Google images, though, the scene looked "tumultuous".
"The fish are writhing around, they have massive teeth, and are pretty scary."
He continued: "With the fishes, it looks like they are struggling for survival.
"It is red in tooth and claw.
"Richmond was obviously driving at something else."
Simon Carter then went on to say how, when the mosaic was commissioned in 1890, Charles Darwin's theories were still controversial.
At the time, the Church was still grappling with his work, The Origins of Species, that had been published 40 years prior.
The Church of England apologised for dismissing the work and ideas of Darwin in 2008.