How to Redeem:
Sign-up or sign-in to your Skype account. Then go to: https://secure.skype.com/wallet/account/voucher.
Enter your gift card code then select, 'Redeem'.
Your gift card balance will be applied as Skpye credit.
How to check your balance:
Sign-in to your Skype account.
Select your profile picture and go to 'My Account'.
Your Skype Credit balance is shown under Skype to Phone.
Open the Skype app and sign-in.
Go to 'Calls'. Your Skype Credit balance is shown beside Skype to Phone.
Abridged terms and conditions:
Redeemable for use only on Skype.
Skype Help: https://support.skype.com/en/contact-us/