The Honduran midfielder missed his side's past two warm-up defeats to Turkey and Israel with a thigh strain.
Honduras have even called up a replacement player, Edder Delgado, who is now on standby after their medical staff assessed Peralta. But the 25-year-old is convinced he will prove his fitness ahead of the tournament this month.
"I have faith I will play at the World Cup," he said. "I have not played for a while because of medical advice, but I hope to return to full training today.
"I feel great and I know I will be good to play in Brazil."