Preheat the air fryer to 400°F (200°C) for 3 minutes.
Place the frozen french fries in a large bowl.
Drizzle the vegetable oil over the fries and toss to coat evenly.
Transfer the fries to the air fryer basket in a single layer, ensuring they are not overcrowded.
Cook the fries at 400°F (200°C) for 15 minutes, shaking the basket halfway through the cooking time to ensure even crisping.
After 15 minutes, check for desired crispiness. If needed, cook for an additional 2-3 minutes.
Remove the fries from the air fryer and immediately sprinkle with salt. Toss gently to distribute the salt evenly.
Serve hot.