How to Test a Proxy: Speed, Geolocation, Anonymity and IP Reputation

Before you start work on new proxies, it is worth testing them: do they work, how fast do they respond, which country do websites see, do they leak your real IP, and is the address on any blacklists? Here is each check — which tools to use and what to look for.

Does the proxy work?

The fastest way to check a whole list is our converter with a proxy check. Paste the lines, and a table appears under the converter: which proxies are alive, their external IP, country and response time. Up to 1,000 proxies are checked at a time, and the "Only live proxies in the result" option keeps only the working ones in the list. If a line has no protocol, the check tries SOCKS5 first, then HTTP.

To check a single proxy, curl is handy — the command shows the IP that websites see:

curl -x socks5h://login:pass@host:port https://api64.ipify.org

If a proxy "doesn't respond", the usual causes are the wrong protocol or port, a mixed-up login and password, or an expired term or used-up traffic. For IPv6 proxies there is one more: the checking service itself has no IPv6.

IPv6 proxies need services with IPv6

An IPv6 proxy only opens websites with IPv6, and checking services are no exception. We tested popular services on 8 October 2026:

If a service from the right-hand column won't open through an IPv6 proxy, the proxy isn't broken — the service simply has no IPv6.

Speed

A proxy's speed has two measures:

• latency — how long you wait for a response. It matters for scraping and any work with lots of small requests;
• throughput — how much data per second you can download. It matters for heavy pages, video and downloads.

Our check shows the latency for the whole list in its response time column. To measure both for a single proxy, download a 10 MB test file with curl:

curl -x socks5h://login:pass@host:port -o /dev/null -s \
  -w "first byte: %{time_starttransfer} s\nspeed: %{speed_download} bytes/s\n" \
  "https://speed.cloudflare.com/__down?bytes=10000000"

For a fair estimate, take several measurements at different times and compare them with the same request without a proxy. Distance has the biggest effect on speed: from you to the proxy server and from the server to the website. If both you and the website are in Europe but the proxy is in the US, the latency will be noticeable — pick a proxy country close to the website or to yourself.

Geolocation

Websites work out the country and city of an IP from geolocation databases — MaxMind, IP2Location, DB-IP and others. The databases update differently and sometimes disagree, especially on cities and on new IPv6 ranges. So:

• check the country on two or three services — for example, ipapi.co, ip.sb and whatismyipaddress.com through the proxy itself;
• trust the country first: the city from an IP is almost always approximate;
• remember that a website uses its own database, which may differ from the one the checking service showed.

You can also check without the proxy: paste the proxy's IP into the lookup on any geolocation database's website.

Anonymity

A proxy replaces your IP, but your real address can leak in other ways:

• Request headers. Some proxies add headers such as X-Forwarded-For or Via containing your IP. On https:// websites the proxy carries traffic through an encrypted tunnel and can't add anything to it. Netrun proxies run in anonymous mode and don't add such headers.
• WebRTC leak. The browser can tell the website your real IP, bypassing the proxy. Check on ipleak.net or browserscan.net: your real address must not appear in the WebRTC section.
• DNS leak. DNS queries may go through your provider rather than the proxy. ipleak.net shows which DNS servers the website sees. In scripts, use socks5h:// or an HTTPS proxy — the proxy then resolves the website's name itself.
• Browser mismatches. The browser's time zone and language don't match the IP's country. You can see this on iphey.com or pixelscan.net.

IP reputation

Reputation means whether an address has been blacklisted for spam, attacks or fraud. You check it without a proxy — just paste the IP into the service's lookup:

• Spamhaus — the largest lists of addresses seen spamming and attacking;
• AbuseIPDB — abuse reports about an address from server administrators;
• IPQualityScore and similar — risk scores used by anti-fraud systems.

Two things worth knowing in advance:

• for IPv6, many lists rate not a single address but a whole /64 subnet;
• services label an address "data centre" or "hosting" when it belongs to a server. For server proxies, IPv6 ones included, that is normal and doesn't mean the address is "dirty". If you need an address that looks like an ordinary subscriber, use mobile proxies.

A quick checklist

1. Run the list through the proxy check — are they all alive?
2. Open api64.ipify.org through the proxy — do you see the proxy's IP, with colons for an IPv6 proxy?
3. Does the country match the one you need on two or three services?
4. In the browser or anti-detect profile, does ipleak.net show no WebRTC or DNS leak?
5. Is the address absent from Spamhaus and AbuseIPDB?
6. Do the websites you need work over IPv6? Check them with the IPv6 test.

FAQ

Why won't whoer.net open through my proxy?

whoer.net has no IPv6, and IPv6 proxies only open websites with IPv6. Use ipleak.net, browserscan.net or iphey.com instead.

A service shows the wrong country. Is the proxy from the wrong country?

Not necessarily: geolocation databases disagree, especially for IPv6. Check on several services — if most of them show the country you need, all is well.

Why does the check say "data centre"?

Because IPv6 proxies run on servers, and that is an honest answer. For websites that block such addresses, mobile proxies are the right choice.

For how line formats and protocols work, see the guides on proxy formats and "HTTP, HTTPS or SOCKS5".