Three months into running my website, my traffic fell off a cliff.
Not slowly. Overnight. One day, I had my usual visitors coming in. The next morning, the numbers were almost zero. I checked everything I could think of — my hosting, my articles, my social media links. Everything looked normal on my end.
It took me two days to find the real problem. My website had been added to a security blacklist. And until I checked, I had no idea it was even possible for that to happen to a small site like mine.
If your traffic has dropped suddenly, or a friend told you their browser showed a warning when visiting your site, this guide is for you. I will explain what a blacklist is, why it happens to ordinary websites, and exactly how to check if yours has been flagged — for free, in under a minute.
What Is a Website Blacklist?
A website blacklist is a list of sites that have been marked as dangerous or untrustworthy. Several organisations keep these lists. The biggest ones include Google Safe Browsing, Spamhaus, McAfee SiteAdvisor, and Norton Safe Web.
When your website appears on any of these lists, serious things start happening:
Visitors using Chrome, Firefox, or Safari see a large red warning page that says something like "This site may harm your computer." Most people close that page immediately — they never reach your content.
Google may quietly remove your pages from search results. Your rankings drop, sometimes completely.
If you send emails from your domain, those emails may land in spam folders or get blocked entirely.
All of this can happen without you knowing — until the damage is already done.
How Do Websites Get Blacklisted?
This is the part that surprised me most. You do not have to do anything wrong to end up on a blacklist.
The most common reason is malware. Hackers target small websites because owners are less likely to have strong security. They inject hidden code into your site — code that redirects visitors to harmful pages or downloads dangerous files onto their devices. Your visitors get hurt. Your website gets blacklisted.
Another common reason is a compromised hosting server. If your website shares a server with other sites, and one of those sites gets infected, the entire server's IP address can be blacklisted — including yours.
Spam is another cause. If someone uses your domain name to send bulk spam emails without your knowledge, email blacklists flag your domain. Suddenly, your legitimate emails stop reaching people.
The unfair truth is that innocent website owners get caught in these situations every day. The important thing is to check regularly and act quickly when something is wrong.
Read related articles:
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How to Check If Your Website Is Blacklisted
I want to keep this as simple as possible, because it really is simple.
Go to the Blacklist Lookup tool on Rankests — rankests.com/blacklist-lookup
Type your domain name into the box and click the button. The tool checks your website against dozens of blacklist databases at the same time. Within seconds, you get a clear result showing whether your site is clean or flagged.
No account. No payment. No technical knowledge needed.
Do this check at least once a month. It takes 30 seconds and can catch a problem weeks before you would notice it on your own.
Pro Tip: Check your domain name and your website's IP address separately. Sometimes only the IP address gets blacklisted while the domain looks clean. The Rankests tool checks both.
What to Do If Your Site Is on a Blacklist
Finding your website on a blacklist feels stressful. But it is a solvable problem. Here is the exact process I followed:
Clean your website first. Before requesting removal from any blacklist, you must fix the actual problem. Scan your website for malware using a tool like Sucuri SiteCheck or your hosting provider's built-in scanner. If malware is found, remove it or restore your site from a clean backup. Update all your plugins, themes, and software to the latest versions.
Submit a removal request. Each blacklist has its own removal process. For Google Safe Browsing, open Google Search Console, go to the Security Issues section, confirm you have fixed the problem, and click Request Review. For Spamhaus and other email blacklists, visit their websites directly and follow their delisting steps. Most removals happen within 24 to 72 hours once your request is approved.
Verify the removal. After 48 hours, run the Rankests blacklist check again. Make sure your website is fully cleared before you consider the matter closed.
How to Protect Your Website Going Forward
After going through this experience, I made four changes that have kept my websites safe ever since.
I update every plugin, theme, and software version as soon as a new release comes out. Outdated software is the most common entry point for hackers.
I use strong, unique passwords for my hosting account, admin dashboard, and email. A weak password is an open door.
I back up my website every week. If something goes wrong, I can restore a clean version quickly and limit the damage.
And I run a blacklist check every month without fail. The Rankests Blacklist Lookup tool makes this so quick that there is no excuse to skip it.
The Key points
A blacklisted website is not permanent. But the longer it stays on a list, the more traffic, rankings, and trust you lose. Checking takes 30 seconds. Recovering after weeks of damage takes much longer.
Run your free check now at rankests.com/blacklist-lookup — type your domain, click check, and know exactly where your website stands today.