New USPS API

The USPS Web Tools migration deadline has passed. USPS now directs developers to REST/JSON APIs authenticated with OAuth 2.0. If your shipping rates still depend on the old USPS Web Tools API, create new USPS API credentials before the next production change or credential rotation.

In this guide, we'll show you how to obtain access to the current USPS API. The OAuth credentials you'll need are the Consumer Key and Consumer Secret.

First, log in to the USPS Developer Portal. If you don't have an account already, you will need to create one. Once you're logged in, click Apps on the top menu bar and then click Add app.

The application name can be anything. We recommend using the name "solvingmaze" for record keeping. Leave the "Callback URL" field empty and tick the "Public Access I" checkbox. Click the "ADD APP" button to submit.

You should now see the app you've created with status set to "Approved".

Click "Edit" to view the app, and then select the "View" tab to view your credentials:

Your USPS OAuth credentials (Consumer Key and Consumer Secret) will be displayed here. Make sure to copy and save them in a secure location.

Once you have your USPS OAuth credentials (Consumer Key and Consumer Secret), you can use SolvingMaze to help you estimate postage by factoring in box sizes and packaging costs. To set up for USPS shipping rates at SolvingMaze, select USPS API for Shipping Rates API in your SolvingMaze menu, and enter your USPS account number and API credentials.

Ready to try SolvingMaze? Create Free Sandbox Warehouse and test packing and quoting, batch picking, and layout simulation before production.