Before pointing a scraper at a target, verify the proxy actually does what the label says: right country, real rotation, acceptable latency, working IPv6. These scripts test all of it from the command line.
curl -x "http://USER:[email protected]:9000" https://ipinfo.io/jsonRun it twice on the rotating port — the IP must change. On the sticky port (:10000 with a -session- username) it must not. There's also a browser-based IP checker that shows your current IP, geo and ASN at a glance; background on the plumbing in what an IP address reveals.
for cc in us gb de jp br; do curl -s -x "http://USER-country-$cc:[email protected]:9000" \ https://ipinfo.io/json | python3 -c "import sys,json; d=json.load(sys.stdin); print('$cc ->', d['country'], d['ip'])" done
Every line must echo its requested country. Full script with rotation and latency checks: check.py.
Two IPs in the same city can behave completely differently depending on their fraud-score history — that's why some "working" proxies still get blocked everywhere. Primer: IP quality score explained, and what IP rotation actually buys you.
IPv6 proxies are dramatically cheaper per IP, but only ~half the web accepts them. Test any target's IPv6 support with the IPv6 compatibility checker before buying; the trade-offs are in the IPv6 proxies guide and plans at quantumproxies.io/ipv6-proxies.
Test against QuantumProxies residential proxies — transparent per-GB pricing, credentials in minutes at app.quantumproxies.io/register.