Step 1: Open the product’s detail page.
In this tutorial, we use this product URL as an example:
https://aliexpress.com/item/1005004146153809.html
Step 2: Get AliExpress Seller ID.
Click F12
and select the console tab. Enter
window.runParams.data.commonModule.sellerAdminSeq
The number line that appears below is the seller ID.