Fresno County sheriff's deputies arrested Robert Joseph Cervantes, Jr., acting on information from those tipsters.
Video shows Cervantes -- with his face uncovered -- walking into the store on Highland on March 24 and then walking out.
As he lingered outside, a woman went into the store, and when she stepped out with her hands full of items she just bought, he charged at her with a knife and tried to take her car.
She ran back inside the store, hustled into the bathroom, and locked the door.
Cervantes also went back in the store, this time covering his face.
The surveillance video shows him jumping over the counter, holding the knife, and pointing to the cash registers.
The clerk gave him some money and he eventually left.
Detectives released the video a couple of weeks later and two people who said they saw it on ABC30 called in tips identifying Cervantes as the suspect.
Prosecutors charged him with robbery and trying to steal the car.
"Without the help of Crimestoppers, ABC30 reporting, and good Samaritans, this would have been a much more difficult case to prove," said deputy district attorney Andrew Janz, who prosecuted Cervantes. "This crime is every clerk's worst nightmare and I trust the judge will do the right thing at sentencing."
A judge will decide Cervantes's punishment on October 28.