Prepare the ingredients: wash and dice the strawberries and pineapple, chop the onion, mince the jalapeño, and chop the cilantro.
Combine the strawberries, pineapple, red onion, and jalapeño into a mixing bowl.
Add chopped cilantro and lime juice to the bowl, and sprinkle salt over the mixture.
Mix all ingredients gently until well combined, tasting for seasoning adjustments.
Let the salsa sit for at least 20 minutes before serving.
Serve the salsa chilled, accompanied by tortilla chips or atop grilled meats or fish.