How to Check IP Purity: A Self-Check Checklist

"Purity" and "risk score" are often used interchangeably, but they're really two sides of the same coin: purity describes whether an IP "has been dirtied," while the risk score quantifies that purity into a 0–100 number. The higher the purity, the lower the risk score.

This article breaks purity into a checklist you can tick off one item at a time, walking you through each with IP You (ipyou.net). The core conclusion first: purity is a "wooden barrel" — fail any single item and the whole thing is wasted.

The purity checklist: all must be ✓ to count as clean

1. Not a proxy exit (HTTP / SOCKS): shared proxies are the number-one killer of purity.
2. Not a VPN range: nearly every commercial VPN IP range is flagged by the platforms.
3. Not a Tor exit node: Tor exits are publicly listed, giving them the lowest purity.
4. No threat-intel blocklist hit: a hit means a confirmed abuse record.
5. No vpn / proxy / socks keywords in the hostname: the reverse-DNS name will "give away" its identity.
6. Consistent ownership, not a datacenter range: a datacenter IP disguised as residential takes a purity hit.

IP You turns the first 5 items into lookup fields: VPN / proxy / Tor hits come from dedicated open-source range databases and public exit lists, the blocklist comes from a large-scale threat-intel database, and the hostname comes from live reverse DNS.

Why the "weakest link" effect is so critical

Purity isn't an average — it takes the weakest link. An IP that passes the first 5 items and hits just 1 blocklist gets its risk score pushed straight into the high-risk band, and the "clean" from the other 5 items is almost entirely wasted. Because to a platform, a single confirmed bad record is enough to make the IP untrustworthy.

Example: the clean-looking "trap IP"

Look up an IP: type = home broadband, not a proxy / VPN / Tor, and a clean hostname — 4 of the first 5 items are ✓. But it hit 1 blocklist. Many people order it as soon as they see "home broadband," then find it repeatedly triggers verification when signing up for accounts. The reason is that 1 blocklist hit — this home broadband address was used by a previous user to do bad things, and the stain hasn't washed off yet.

How purity relates to the risk score

Think of it this way: purity is the "cause," the risk score is the "effect." For every ✗ on the checklist, the risk model adds points or applies a floor accordingly, which ultimately shows up in the risk score. So when checking purity, look at both the item-by-item checklist results and the final risk score — the former tells you "where it's dirty," the latter tells you "how dirty."

What to do when purity is low

• Blocklist hit: for home broadband, re-dial for a new IP; for a proxy / cloud host, switch to an address that isn't listed.
• Flagged as proxy / VPN: switch to a native residential line — don't use a shared commercial VPN exit.
• It's a datacenter range: for high-scrutiny uses, always switch to home broadband / premium residential.
• Always re-check after switching: confirm the whole checklist turns ✓ and the risk score has dropped before putting it to use.

Check purity with IP You

1. Open ipyou.net and look up the target IP.
2. Match the result's proxy / VPN / Tor flags, blocklist hits, IP type, and hostname against the checklist, ticking off each item.
3. For any ✗, weigh it against the risk score to decide whether to switch — especially a blocklist hit, which almost always means switching.
4. After switching IPs, return to step 1 and re-check until the whole checklist is green.