Free online proxy checker

Your checkout keeps failing at the payment step. You've tried different proxies, but nothing works. The issue isn't proxy quality, it's whether your proxy behavior matches what the site validates. Sites check IP consistency, request patterns, or both. Test what your target site validates, then choose sticky or rotating accordingly. You'll see how to validate site requirements, avoid common mistakes, and pick the right strategy for eCommerce checkouts, web scraping, social media management, and API integration. Here's the testing process.