The Tool Desk
Outbyte Driver Updater FREEScan for outdated or missing drivers - takes under a minuteDriver Scan →Outbyte PC Repair FREERepair Windows errors before they cause bigger problemsFix Now →An IP blacklist checker tests an email-sending IP address against one or more spam blocklists, commonly called DNS-based blocklists (DNSBLs) or real-time blocklists (RBLs). To get a useful answer, check the IP that actually sends your mail, note the specific list and whether it reports an IP or a domain, then confirm any listing with that list operator’s own lookup and guidance.
What an IP blacklist checker checks
A checker queries the address you provide against the blocklists covered by that service. A multi-list lookup is useful for broad screening: MXToolbox says its email blocklist check covers more than 100 DNS-based email blocklists, but that is a service coverage claim, not a count of every blocklist in existence. MXToolbox’s Email Blocklist Check
As an Amazon Associate I earn from qualifying purchases.
A result is not a universal verdict on deliverability. A listing may affect delivery when a receiving mail system uses that list, but the lookup alone does not show that every recipient will reject your messages. Likewise, a clean result only means the queried address was not reported on the lists checked; it does not guarantee inbox placement.
Free tools Windows power users keep installed
One-click scans. No signup required.
Find the IP address that sends your email
Use the public outbound sending IP—not automatically the IP hosting your website or the address of an inbound mail server. A website can use one provider while its email is sent through another. If you use a hosted email service, consult its sending or delivery settings, logs, or support documentation. If you operate your own mail server, inspect its outbound configuration or delivery logs.
#1 Best Overall
- Compact and Efficient Design: The FortiGate 40F is designed for small to mid-sized businesses and enterprise branch offices, featuring a compact, fanless desktop form factor that ensures quiet operation and minimizes space usage.
- Robust Connectivity Options: Equipped with 5 GE RJ45 ports, including 1 WAN port and 4 internal ports, this model provides essential connectivity and flexibility for various network configurations in a small-scale environment.
- High-Performance Security: Offers up to 1 Gbps IPS throughput and 600 Mbps threat protection throughput, using Fortinet’s purpose-built security processor technology to deliver industry-leading performance and protection for SSL encrypted traffic.
- Advanced Threat Protection: Integrated with Fortinet’s AI-powered FortiGuard Labs, the FortiGate 40F offers comprehensive cybersecurity, identifying and mitigating both known and unknown threats to maintain robust security across your network.
- Simplified Management and Deployment: Features a user-friendly management console that provides comprehensive network automation and visibility, coupled with Zero Touch Integration with Fortinet’s Security Fabric for easy deployment.
If you do not know which mail infrastructure handles your domain, an MX lookup can help identify the servers configured to receive mail. MXToolbox recommends starting with an MX lookup when the mail-server address is unknown. However, an MX record identifies inbound mail routing; it does not necessarily identify the public IP used for outbound delivery. MXToolbox’s lookup guidance
Run the lookup and confirm the list
- Start with the actual sending IP. Enter the outbound public IP in a multi-list checker to screen across the lists it covers.
- Read the exact result. Record the list name, the queried target, and any explanation or link provided. If a bounce message names a particular list, check that list directly rather than assuming every multi-list service includes it.
- Use the operator’s own lookup. For a Spamhaus-related result, use the Spamhaus IP and Domain Reputation Checker and follow the explanation associated with the specific dataset. Spamhaus describes its checker as a way to look up current IP and domain entries. Spamhaus general dataset FAQs
- Verify unexpected DNS results carefully. Confirm that the IP and DNSBL zone are correct, and use the list operator’s supported query method. Spamhaus warns that misspelled DNSBL names can mislead and that some public resolvers, including Google Public DNS, may return a not-listed response for its public DNSBL servers. A raw DNS answer from an unsupported resolver may therefore not settle the question. Spamhaus DNSBL usage FAQs
Check whether the result is for an IP or a domain
An IP blocklist result and a domain blocklist result are different findings. Make sure the checker’s target matches the type of list and the evidence in your bounce or mail-server log.
Rank #2
- HARDWARE PLUS SECURITY SERVICES: FortiGate-60F Firewall Appliance bundled with 1 year of FortiCare Premium and FortiGuard Unified Threat Protection.
- UNIFIED THREAT PROTECTION (UTP): Secures against advanced online threats with comprehensive web filtering and anti-botnet technologies.
- OPTIMIZED FOR MEDIUM-SIZED BUSINESSES: Tailored for businesses needing robust security without the infrastructure of larger enterprises.
- RELIABLE CUSTOMER SUPPORT: FortiCare Premium ensures high-quality support and service continuity.
- EFFECTIVE PROTECTION: Employs advanced filtering technologies to safeguard against sophisticated threats.
- IP listing: The entry concerns a numerical address used by a sending server. Check the outbound IP and the operator’s explanation for that listing.
- Domain listing: The entry concerns a domain name, which may appear in message content or other domain-related data. It does not establish that a particular sending IP is listed.
Spamhaus’s Domain Blocklist (DBL) is domain-based: “No IP addresses are listed in the DBL.” For an IP DNSBL lookup, Spamhaus points users to ZEN. Use the list type that corresponds to the target you need to investigate. Spamhaus DBL and IP DNSBL FAQs
Do these 3 things before closing this tab:
1Clear out junk files and repair common Windows errors2Fix the driver behind crashes, sound loss and screen glitches3Repair Windows errors before they cause bigger problemsInterpret the listing before taking action
Do not treat every listing as proof that a server is malicious. The list’s purpose and reason matter. For example, Spamhaus’s Policy Blocklist (PBL) can identify IP addresses that should not send email directly to third-party mail exchangers under the relevant policy. Spamhaus says PBL entries are not necessarily bad; they may indicate that mail should be sent through the provider’s designated mail service instead. Spamhaus Policy Blocklist
Rank #3
- 【Up to 1100 Mbps VPN Speed 】 Hardware-accelerated WireGuard and OpenVPN-DCO deliver up to 1100 Mbps VPN throughput, over 3× faster than Brume 2 for smooth remote access and file transfers.
- 【Three 2.5G Ports & Multi-WAN】Tri-port 2.5GbE design with flexible WAN LAN configuration supports multi-gigabit wired setups, dual-ISP Multi-WAN and failover to keep home and SOHO networks online.
- 【Stealth VPN Obfuscation】VPN obfuscation disguises VPN traffic as regular HTTPS, helping you evade blocking, bypass restrictive networks and maintain stable, private connections.
- 【DPI protection】Deep Packet Inspection with visual dashboards blocks adult/gambling/malicious sites, while SQM and QoS prioritize gaming, calls, and video when bandwidth is tight
- 【OpenWrt & USB 3.0 Expansion】OpenWrt with 1GB DDR4 and 8GB eMMC lets you install plugins and build VPN, ad-blocking or NAS, while USB 3.0 Type‑C connects high-speed storage or 4G/5G dongles
For other listings, consult the operator’s current entry details and the mail-delivery evidence. A checker identifies a result; it does not by itself explain the cause, establish how a specific recipient handles the list, or determine whether the address is being used appropriately.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.What to do if your sending IP is listed
- Read the operator’s entry and policy. Identify what the list says the listing represents and whether it provides a removal or appeal path.
- Address the underlying issue first. Review mail logs, sending configuration, account security, and the source of unexpected traffic as relevant to the operator’s stated reason. If the entry is policy-based, use an authorized outbound mail route rather than trying to treat it as an abuse finding.
- Follow that operator’s removal process. Supply the requested information and make only changes you can verify. Spamhaus directs users to its reputation checker for listing and removal guidance; other operators may have different processes. Spamhaus DBL and IP DNSBL FAQs
- Recheck and monitor delivery evidence. Confirm the result with the operator’s lookup and review subsequent bounces or delivery logs. No universal removal time or guaranteed restoration of delivery is established; both depend on the list and the receiving systems involved.
When a multi-list check is not enough
Use a broad lookup to discover possible listings, but treat the named operator as the authority on its own data and remediation. A multi-list result may not cover the list named by a recipient, while an operator-specific checker addresses that operator’s datasets. If you administer a mail server and need to test whether it is configured to use Spamhaus DNSBLs, Spamhaus Technology provides a separate Blocklist Tester; that checks DNSBL configuration, not whether an IP is listed. Spamhaus Technology Blocklist Tester
Quick Recap
Product prices and availability are accurate as of the date/time indicated and are subject to change. Any price and availability information displayed on Amazon at the time of purchase will apply.
