Before an address can be certified as deliverable (CASS-certified), it must first be standardized.
Standardization converts an address to a standard format by correcting the address, if possible, and adding missing information, such as a ZIP code, to produce a complete address containing a street address, city, state, and ZIP code.
Break your list of addresses into manageable parcels (eg. Item numbers correspond to original input file for easy reference.
SAVE EACH RECORD INDIVIDUALLY TO GENERATE FINAL OUTPUT FILE!!!
Please note that you are not limited to validating email addresses: you can also review products and services, reply to event invitations, and much more.
For more information, please visit our documentation at https://developers.google.com/gmail/actions.
This is different from the credit card Address Verification System (AVS), which is the method used by credit card processors to authenticate ownership of a credit card by verifying that the account on the credit card matches the billing address on file.
Credit card AVS does not determine deliverability of an address.
You will need a developer API key, but you can get that for free. Their API allows up to 5,000 requests per day free of charge.