0spam — Check, Delist & Monitor
Check if you're listed on 0spam DNSBL. Auto-delists within 24 hours, or request one free manual removal every 3 hours. Monitor your IP reputation automatically.
Impact & Usage
Used by over 1 million mail servers worldwide via free DNSBL queries. A listing here can cause rejections across a broad, diverse set of receiving servers.
Typical users: Over 1 million mail servers worldwide; free for commercial and non-commercial use with no query limits
What Gets You Listed
Automated detection of spam-sending IPs via distributed sensor network; listed when spam volume exceeds thresholds
How to Get Delisted
- Check your listing status at 0spam.org by entering your IP address.
- Identify and fix the root cause — compromised accounts, misconfigured mail servers, and spam script infections are the most common triggers.
- Submit a free manual removal request at 0spam.org/request. You can request one removal every 3 hours per IP.
- If you prefer to wait, listings auto-expire within 24 hours once spam activity stops. Verify removal with mxio Blacklist Check.
Expected Timeline
24 hours (automatic) or immediate (one free manual removal per 3 hours)
Auto-delist: Automatic removal within 24 hours of spam cessation; one free manual removal per 3 hours via website
Common Causes
- Compromised email account sending outbound spam through your mail server
- Web application vulnerability (contact forms, registration pages) exploited for spam relay
- Mail server misconfiguration allowing unauthorized relay or missing authentication
Prevention Tips
- Enforce strong authentication on all email accounts and monitor for unusual sending patterns
- Rate-limit outbound mail from web applications and implement CAPTCHA on public forms
- Keep mail server software updated and regularly test that relay restrictions are working
Overview
0spam is a free, community-driven DNSBL that has quietly become one of the more widely deployed blacklists on the internet. With over a million mail servers querying it, a 0spam listing has genuine reach — not as concentrated as Spamhaus or Barracuda in the enterprise space, but spread broadly across hosting providers, small businesses, and independent mail administrators who use free DNSBLs as part of their filtering stack.
The list relies on a combination of spamtrap data, automated traffic analysis, and community reporting. When an IP is flagged, the listing auto-expires within 24 hours provided the spam activity stops. For faster resolution, 0spam offers one free manual removal request every 3 hours — a generous policy compared to many lists that either charge for express removal or offer no manual option at all.
Because 0spam's user base skews toward smaller, independently managed mail servers, a listing here may not show up immediately in bounce logs from large providers like Gmail or Microsoft 365. However, you may see intermittent rejections from business mail servers, hosting companies, and regional ISPs. If you are listed on 0spam, investigate the root cause even if your delivery to major providers seems unaffected — the same behavior that triggered 0spam will eventually attract attention from higher-impact lists.
Monitor Your Blacklist Status
Get alerted the moment your IP or domain appears on a blacklist. Catch listings early, before they impact deliverability.
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