Question 1

What is an email blacklist?

Accepted Answer

An email blacklist (or blocklist/DNSBL) is a real-time database of IP addresses and domains that have been reported for sending spam. Email servers check these lists when receiving messages — if your IP or domain is listed, your emails may be blocked or sent to spam.

Question 2

How do I get removed from a blacklist?

Accepted Answer

Each blacklist has its own delisting process. Most require you to submit a removal request and prove you've fixed the underlying issue (compromised server, poor list hygiene, etc.). Some lists automatically delist after a period of no spam activity. ColdRelay monitors blacklists 24/7 and handles delisting for your sending infrastructure.

Question 3

Why is my domain listed even if I haven't sent spam?

Accepted Answer

Shared IP addresses (common with cheap hosting), inherited domain reputation, or DNS misconfigurations can cause false listings. This is why dedicated sending infrastructure with proper authentication (SPF, DKIM, DMARC) is critical for cold email.

Question 4

How often should I check my blacklist status?

Accepted Answer

For active cold email campaigns, check at least weekly. Listings can happen at any time and the sooner you catch them, the less impact on your deliverability. ColdRelay automates this with continuous monitoring and instant alerts.

Question 5

Does this tool check all blacklists?

Accepted Answer

This tool checks 12 of the most commonly used and impactful email blacklists. There are hundreds of smaller lists, but these cover the ones that major email providers (Gmail, Outlook, Yahoo) actually reference when filtering mail.

Email Blacklist Checker

Frequently Asked Questions

Going deeper on blacklists

ColdRelay Monitors Blocklists 24/7 For You