Enter a 20-digit A-key and the ESN to get the 6 check digits a handset expects during manual A-key entry. Enter all 26 digits to verify an existing entry.
Everything is computed in your browser. The A-key and ESN are never sent to a server.
The check digits depend on the ESN the network authenticates. When the card is set to use its UIM_ID in place of the handset ESN, enter the UIM_ID. The network's authentication center must hold the same A-key and ESN.