If you want to check whether both PAN card and Aadhar card number are linked or not, want to know which PAN number is linked to Aadhar card or want to check mask Aadhar from PAN number, for this you can visit eportal.incometax.gov. You can go to the .in site where you can check the PAN Aadhaar link for free, if you want to know something else then you can log in and see.