Baker's time of 30.57 seconds, in her semi-final, was 0.26 seconds faster than the previous world best set by South Africa's Penny Heyns in 1999 and half a second better than anything she had ever achieved.
"Today in the pool I thought I could do something special and I did," said the Sheffield swimmer.
"I coach myself now so I do all the things that I want to do. I know my body better than anybody else.
"I don't care about records tomorrow, I've done what I needed to do.
"I'll have to go for the gold on Wednesday."
In the other semi, Australia's Leisel Jones may be Baker's closest challenger in final, although her time of 31.99 was over a second slower than that of the Englishwoman's.
In the women's 50m butterfly, Australians Petria Thomas and Nicole Irving look to battle it out for gold after winning their respective semi-finals.
In the men's 50m backstroke semi-finals, Australia's Matt Welsh set a new Commonwealth record of 25.86 seconds moments after Canada's Riley Janes did to win his race.
Expect those two swimmers to run each other close for the gold.