Data-provider / third-party services
While third-party tools exist, the safest and most reliable methods involve using official PayPal features or direct observation. How do I confirm my email address? | PayPal US paypal valid email checker
Free tools are often loaded with malvertising, drive-by downloads, or browser hijackers. One click and your device is compromised. paypal valid email checker
The existence of these tools forces platforms to implement robust security measures. paypal valid email checker