Also the ring fits both Gollum and Bilbo, which limits how different in size they could be.
(LOTR says the ring can change size, but this wasn't discussed in the Hobbit, and presumably hadn't occurred to Tolkien yet when he wrote it).
(LOTR says the ring can change size, but this wasn't discussed in the Hobbit, and presumably hadn't occurred to Tolkien yet when he wrote it).
In LotR it’s revealed that he rarely wore it anymore by that time.
Its on such an expedition that the ring "slips" from him, further suggesting the ring is actually not only his size, but a little large.
It's heavily implied in LOTR that the ring is able to change it's size to cause itself to slip from a person's finger, though that's somewhat out of scope and the illustrator may not have read that.