Bots and automation
Bulk sign-ups, fake reviews and spam usually run through rented proxies.
What counts as a proxy
A proxy forwards someone’s traffic so your site sees the proxy’s address instead of theirs. Proxies are bought in bulk to run bots, scrape content, create accounts and test stolen cards, often rotating through thousands of addresses.
VPN Blocker flags addresses in networks that sell or run proxies with the proxy category, and flags data center addresses, where most cheap proxies run, with host-ip set to true.
const r = await lookup(ip);
// A network that sells or runs proxies
r.categories.includes('proxy');
// A data center address, where most proxies run
r['host-ip'] === true;
// How sure we are, so you choose how strict to be
r.confidence;How to check for a proxy
Treat the visitor as a proxy when categories contains proxy, and catch data center proxies too with host-ip.
JavaScript
const r = await lookup(ip); // see the guides for lookup()
const isProxy = r !== null && (r.categories.includes('proxy') || r['host-ip'] === true);PHP
$r = vpnblocker_lookup($ip); // see the guides for vpnblocker_lookup()
$isProxy = $r !== null && (in_array('proxy', $r['categories'], true) || $r['host-ip'] === true);Python
r = lookup(ip) # see the guides for lookup()
is_proxy = r is not None and ("proxy" in r["categories"] or r["host-ip"] is True)Full walkthroughs: PHP · Node.js · Python · game servers and Discord
Why sites block proxies
Scraping
Scrapers rotate through proxy addresses to get around rate limits. Slow them down or ask for a captcha.
Card testing
Fraudsters test stolen cards on checkout pages through proxies, a few attempts per address.
Promo and referral abuse
One person claiming a coupon or referral bonus hundreds of times.
Sneaker and ticket bots
Keep limited releases for real customers.
Ad and click fraud
Leave proxy traffic out of your analytics and paid-click counts.
Questions
What kinds of proxies do you detect?
Networks run by proxy providers are categorized as proxy. Most cheap and bulk proxies also run on servers in data centers, which we flag as hosting with host-ip set to true. Checking both catches the large majority of proxy traffic.
Can you detect residential proxies?
Only partly. Residential proxies send traffic through real home internet connections, so on their own those addresses look like ordinary home users to any IP-based check. For high-risk actions, combine our answer with other signals such as account age, device checks or a captcha.
What’s the difference between a proxy and a VPN here?
Both hide the visitor’s real address. vpn means a network run by a VPN service for consumers; proxy means a network that sells or runs proxies, usually for automation. An IP can be in more than one category.
Is proxy detection on every plan?
Yes. Every plan, including Free, returns categories, host-ip and confidence.
More detection
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