For accessing USPS APIs, you need to register for a USPS account.
You would be required to put in the following info as shown from the screenshot :
Once the details are put in and you have successfully registered, you’ll receive USPS User ID.
If you are shipping a high volume of packages, you can avail the e-VS facility. More on e-VS service here.
|The e-VS, or Electronic Verification System, allows high-volume package mailers and package consolidators to document and pay postage, including special service fees, using electronic manifest files. The files are transmitted over the Internet to a Postal Service™ database. e-VS is designed to make it easy for high-volume package mailers to take advantage of destination entry rates.|
You can also learn ‘How to apply for EVS here :
If you have any queries, please do contact us.