Summary
Razor2 is a collaborative and distributed spam detection network utilized by SpamAssassin. It identifies spam by comparing message checksums to a database of known spam signatures. A domain is listed when its email content resembles known spam. Direct delisting is not possible; the listing expires automatically once the content no longer matches spam signatures. Being listed in Razor2 can negatively impact email deliverability. Prevention involves focusing on email content, maintaining sender reputation, implementing proper authentication (SPF, DKIM, DMARC), and proactively testing email content for spam triggers.
Key findings
- Content-Based Listing: Razor2 lists domains whose email content resembles known spam.
- No Direct Delisting: There is no direct delisting process available for Razor2.
- Collaborative and Distributed: Razor2 is a collaborative and distributed network; decisions are based on collective reporting.
- Automatic Expiration: Listings expire automatically when the problematic content is no longer detected.
- Impact on Deliverability: Razor2 listing negatively impacts email deliverability.
Key considerations
- Improve Email Content: Review and modify email templates and messaging to avoid spam-like characteristics and reduce similarity to known spam.
- Focus on Sender Reputation: Implement best practices to maintain a positive sender reputation.
- Implement Authentication: Use SPF, DKIM, and DMARC to authenticate email and improve deliverability.
- Proactive Content Testing: Test email content using tools like Mail-Tester before sending to identify and address potential spam triggers.
- Monitor DMARC Reports: Check DMARC reports to identify where your domain is being used and address any unauthorized sending.
What email marketers say
11 marketer opinions
Razor2 is a collaborative spam detection network that identifies spam based on message content. A domain gets listed in Razor2 when its email content resembles known spam. Direct delisting is not possible; the listing expires automatically when the content is no longer identified as spam. Being listed can negatively impact deliverability. Prevention involves monitoring and modifying email content, avoiding spam-like characteristics, using dedicated IPs, proper authentication (SPF, DKIM, DMARC), and testing content before sending.
Key opinions
- Content Matching: Razor2 uses fuzzy checksums to compare email content to a database of known spam signatures. If a match is found, the email may be flagged.
- No Direct Delisting: There is no direct delisting process from Razor2. The listing expires automatically if the content is no longer flagged as spam.
- Impact on Deliverability: Being listed in Razor2 can negatively impact email deliverability by increasing the chances of emails being marked as spam.
- Proactive Prevention: Proactive measures such as using dedicated IPs, proper authentication, and avoiding spam trigger words can help prevent Razor2 listings.
Key considerations
- Monitor Email Content: Regularly audit email templates and content strategies to identify and eliminate elements that may trigger spam filters.
- Review and Modify: Review and modify email templates and messaging to avoid spam-like characteristics.
- Use Proper Authentication: Implement SPF, DKIM, and DMARC authentication to improve sender reputation and reduce the likelihood of being flagged as spam.
- Test Email Content: Use tools like Mail-Tester to test email content before sending to a large audience, identifying potential spam triggers.
Marketer view
Email marketer from SpamFightingForum.com answers that your email content is likely the reason for the listing. Review and modify your templates and messaging to avoid spam-like characteristics.
9 Mar 2025 - SpamFightingForum.com
Marketer view
Email marketer from EmailProvider.com explains being listed in Razor2 can negatively impact email deliverability by increasing the likelihood of emails being marked as spam. Suggests focusing on improving email content and sender reputation.
9 Sep 2023 - EmailProvider.com
What the experts say
3 expert opinions
Razor2, used by SpamAssassin, is a collaborative network identifying spam through message checksums. A domain's listing indicates its content resembles known spam. Direct delisting is impossible; listings expire when content no longer resembles spam. Prevention focuses on email content and sender reputation.
Key opinions
- Collaborative Spam Detection: Razor2 is a collaborative, distributed spam detection network.
- Content Resemblance: Being listed in Razor2 means your email content resembles known spam.
- No Direct Delisting: Direct delisting from Razor2 is not possible.
- Listing Expiration: Listings expire automatically when content no longer resembles spam.
Key considerations
- Focus on Email Content: Ensure your email content is not similar to known spam.
- Maintain Sender Reputation: Implement best practices to maintain a good sender reputation.
Expert view
Expert from WordtotheWise.com shares that avoiding Razor2 listings involves focusing on email content. Ensure your messages are not similar to known spam, and implement best practices to maintain a good sender reputation.
14 Jul 2023 - WordtotheWise.com
Expert view
Expert from SpamResource.com responds that direct delisting isn't possible. Razor2 relies on collective reporting. If your content stops resembling spam, the listing will eventually expire.
4 Jan 2024 - SpamResource.com
What the documentation says
3 technical articles
Razor2 is a distributed and collaborative spam detection network. It works by clients reporting detected spam, which is compiled into a catalog used to filter spam. It uses checksums of email bodies, comparing them against a database of known spam signatures to flag potential spam. Razor2 can be enabled as a plugin within SpamAssassin to enhance spam detection rates.
Key findings
- Collaborative Network: Razor2 is a distributed, collaborative spam detection and filtering network.
- Checksum-Based Detection: Razor2 creates checksums of email bodies and compares them to a database of known spam signatures.
- SpamAssassin Integration: Razor2 can be enabled within SpamAssassin to improve spam detection rates.
Key considerations
- Configuration: Razor2 requires configuration as a plugin to SpamAssassin.
- Content Analysis: Understanding that Razor2 uses checksums of email bodies is crucial for avoiding false positives.
Technical article
Documentation from Razor.sourceforge.net explains that Razor2 is a distributed, collaborative, spam detection and filtering network. Clients report detected spam, and the reports are combined into a Razor2 catalog. This catalog is then distributed to clients, who use it to filter spam.
6 Dec 2022 - Razor.sourceforge.net
Technical article
Documentation from cPanel.net explains that Razor2 can be enabled within SpamAssassin to improve spam detection rates. It's a plugin that needs to be configured.
7 Aug 2023 - cPanel.net
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