Combine the diced mango, tomatoes, red onion, cilantro, jalapeño peppers, lime juice, salt, and pepper (if using) In a medium bowl.
Taste and adjust the lime juice, salt, and pepper to your preference. For more heat, leave some seeds in the jalapeño or add a pinch of cayenne.
For the best flavour, cover and refrigerate the pico de gallo for at least 30 minutes before serving. This lets the flavours meld.
Serve with tortilla chips, tacos, grilled fish, or chicken.