proxycheck.io competitors and alternatives

The alternatives, briefly

Kaidn compared with proxycheck.io

Fast, cheap detection of whether an IP is a proxy, VPN or data centre address, delivered as a simple lookup API.

proxycheck.io is very good at a narrow question, and it is cheap enough that arguing about price is a waste of everyone's time. From €3.99 a month you get ten thousand daily queries, and their free plan runs the same detection as the paid ones rather than a cut-down version.

If what you need is "is this address a proxy", buy it and move on.

This page exists because a lot of teams buy an IP API when what they actually needed was a decision, then spend six months building the rest of the decision themselves.

An address is not a person#

An IP tells you about a connection. It does not tell you that the same person opened forty accounts last week under forty different addresses, that the email was registered eleven minutes ago, or that the phone is a VoIP line already sitting on three other accounts.

Those are different questions, and no IP API can answer them, because the data is not in an IP address. That is not a criticism of proxycheck. It is the edge of the category.

Our response to an event is allow, review or block, with the checks that fired attached. IP reputation is in there, weighted next to email identity, phone, device and repetition. If you only ever look at the IP part of that, you have bought a more expensive proxy checker, and you should buy theirs instead.

The price comparison people usually get wrong#

Their pricing is per daily query. Ours is per scored event per month. Ten thousand queries a day is about three hundred thousand a month, so on raw volume they are dramatically cheaper, and any comparison that hides that is dishonest.

The numbers differ because a Kaidn event is not a lookup. It is a decision across every signal we hold about that user, including signals that required us to have seen other users.

If you are pricing lookups, price lookups. If you are pricing decisions, the unit is not comparable and the cheaper number is not the relevant one.

Where proxy detection stops being the problem#

Teams who outgrow an IP-only answer usually hit the same wall. Their fraud stopped using obvious proxies.

Residential proxy networks route through real home connections, and an address that belongs to a genuine broadband subscriber will never look like a data centre, because it is not one.

At that point what catches the ring is not the address. It is that these accounts share a device, or an email pattern, or arrive together in a burst, or connect to entities another operator already labelled. That is what we built, and it is why we are priced the way we are.

If you are not there yet, you do not need us yet.

The wall, in code#

That moment is specific enough to write down. The check keeps coming back clean and the accounts keep being fake:

const { proxy, type } = await proxycheck(ip);

// residential proxy: proxy=false, type="Residential". Correct, and useless here.
if (proxy) return deny("proxy");
return allow();

What separates the ring at that point is not on the address:

{
  "verdict": "review",
  "score": 62,
  "reasons": ["email_reuse", "aliased_address", "device_reuse", "ip_velocity"],
  "checks": [
    {
      "check": "emailReuse",
      "weight": 25,
      "reason": "email_reuse",
      "message": "This mailbox is behind 4 accounts",
      "evidence": { "accountCount": 4 }
    },
    {
      "check": "emailRisk",
      "weight": 8,
      "reason": "aliased_address",
      "message": "Address uses aliasing tricks that resolve to another inbox",
      "evidence": { "tricks": ["dot_trick", "plus_tag"] }
    },
    {
      "check": "deviceReuse",
      "weight": 22,
      "reason": "device_reuse",
      "message": "This device is linked to 4 accounts, on different networks",
      "evidence": { "accountCount": 4, "sameAsnAccountCount": 1 }
    },
    { "check": "velocity", "weight": 15, "reason": "ip_velocity", "evidence": { "distinct_ips": 6 } }
  ]
}

j.smith+2@gmail.com, j.s.mith@gmail.com and js.mith+x@gmail.com are one inbox. Stripping the dots and plus tags back to the real address is not something an IP API can do, because the email never reaches it.

Score the payout, not only the signup#

The highest-value change for anyone at that wall costs one extra call, and it is not on the registration:

// at registration the farmer has told you almost nothing yet
await kaidn.score({ event: "signup", user_id, ip, email, device_id });

// by the time value moves they have told you a great deal more: which device
// came back, from which network, how fast, against which account.
const { verdict, reasons } = await kaidn.score({
  event: "cashout",
  user_id,
  ip,
  email,
  device_id,
});

if (verdict === "block") return holdPayout(reasons);

One honest caveat, since this page is otherwise about not overselling. Kaidn scores the cashout. It never takes a payout destination. Counting how many accounts withdraw to the same wallet or bank account is your own query, and it is worth writing.

What catches a ring is a Kaidn review or block on the cashout, plus your own count of accounts converging on one destination. Score both ends and you have the first half. Keep a destination index and you have the second.

Where we would send you elsewhere#

If your problem is genuinely at the network layer, buy theirs. If you want rich IP context rather than a yes/no on hiding, IPinfo is the better shape. If residential proxies specifically are what keeps you up, Spur has gone deeper on that than either of us. And if you want a free second opinion on an address, AbuseIPDB costs nothing and takes an afternoon to wire in.