What is the normal balance for contra asset accounts? Debit or Credit?

contra asset accounts should be a credit

contra asset account is a credit nature 

A contra asset account is an asset account where the balance will be either a credit balance or a zero balance. 

(A debit balance in a contra asset account will violate the cost principle.) Since a credit balance in an asset account is contrary to the normal or expected debit balance the account is referred to as a contra asset account.

The most common contra asset account is Accumulated Depreciation Account where balance is mostly credit or can be zero.

CreditA contra asset account is an asset account where the balance will be either a credit balance or a zero balance. Most common account is Accumulated Depreciation.