What is JunkEmailFilter (Hostkarma)?
DNS zone: black.junkemailfilter.com
black.junkemailfilter.com is the blacklist tier of the Hostkarma system operated by Junk Email Filter, a small US filtering company. Hostkarma is built from the company's live filtering and spam-trap network, and it is unusual in publishing positive tiers too: known-good senders resolve on its whitelist zone, mixed sources on intermediate tiers, and observed spam sources on black.
Listings are automated and deliberately short-lived. The project's philosophy is recency: an IP spamming traps today is black today, and an IP that goes quiet falls out of the black data within days, without paperwork. Documentation and lookup tools live on junkemailfilter.com and its wiki.
How serious is a JunkEmailFilter (Hostkarma) listing?
Small to moderate. Hostkarma data is consumed by SpamAssassin plugins and assorted smaller mail systems, typically as one signal among many rather than a hard block. The black tier can tip borderline mail into spam folders at those receivers. As ever with trap-driven lists, the listing's diagnostic message outweighs its direct blocking effect.
Why your IP got listed
Spam-trap hits
Mail from your IP reached Junk Email Filter's trap addresses, pointing at purchased, scraped or badly aged list segments.
Spam classified by their live filtering
The company filters real customer mail; output from your IP that their system classifies as spam feeds the karma data.
A compromised sender
Hijacked accounts and exploited forms produce exactly the burst-of-spam pattern that flips karma to black.
How to remove your IP from JunkEmailFilter (Hostkarma)
Confirm the black listing
Our checker queries the black zone directly; the lookup tools on junkemailfilter.com show the same and sometimes the karma tier detail.
Stop the spam source
Suspend the implicated campaign, purge unengaged and acquired segments, rotate SMTP credentials and inspect outbound queues for mail you do not recognise.
Let the entry age out
Black entries expire automatically within days of the last bad observation. For most senders, no contact is needed at all.
Contact the operator only if it persists
If a listing outlives a verified fix by more than a week, use the contact and wiki instructions on junkemailfilter.com to request review. Small operators respond best to short, factual accounts.
How long removal takes
Automatic expiry within roughly a few days of the last trap hit or spam classification. Manual review, when needed at all, runs on a small operator's timetable. There is no fee in either path.
After delisting: the part most guides skip
Getting off JunkEmailFilter (Hostkarma) removes a block; it does not restore trust. While you were listed, mailbox providers were accumulating their own negative signals about your domain (bounces, spam-folder placements, dropped engagement), and those persist after the listing clears. If placement does not bounce back within a couple of weeks, the domain needs a structured re-warming: reduced volume, genuinely engaged recipients and clean authentication, sustained until providers trust the domain again.
Frequently asked questions
How do I get off the Hostkarma black list?
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Stop the mail that earned the flag; entries age out automatically within days once traps and filters stop seeing spam from your IP. Only chase manual review via junkemailfilter.com if a listing persists well beyond a verified fix.
What are the Hostkarma colour tiers?
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White for known-good senders, black for observed spam sources, with yellow and brown covering mixed or suspicious traffic in between. Receivers can use the tiers for scoring in both directions, rewarding white as well as penalising black.
Will a Hostkarma black flag bounce my mail everywhere?
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No. Its consumers are mostly smaller systems using it as a scoring signal, so the practical effect is added spam-folder risk at those receivers. Treat the flag mainly as fresh evidence of a list-hygiene or compromise problem worth fixing this week.