No. Header parsing and EML/text file reading are performed locally in your browser. The network tabs send only the domain, hostname or IP required for that specific diagnostic.
Free Email Diagnostic Toolkit
Email Diagnostic Tools
Analyze email headers privately in your browser, inspect sender authentication and routing, test mail ports and SMTP capabilities, check DNS email security records, and investigate IP blacklist status.
- ✔ Header Analyzer
- ✔ SPF / DKIM / DMARC
- ✔ Mail Port Tests
- ✔ DNSBL & SMTP Diagnostics
Diagnose Email Delivery, Authentication & Reputation Problems
Paste raw email headers or upload an
.eml / text file to inspect the message route, probable originating IP, SPF, DKIM, DMARC, ARC, TLS and spam-filter headers. Header parsing happens locally in your browser. Network-based checks use only safe PHP DNS, cURL/socket-style functions — no shell commands.Privacy: the Header Analyzer does not upload the message or header to Systron. Uploaded files are read with your browser's FileReader API and analyzed locally.
How It Works
1. Paste or Upload
Paste raw headers or load an .eml file. The analyzer unfolds headers and reads repeated Received and Authentication-Results fields.
2. Inspect Authentication
Review SPF, DKIM and DMARC results, sender/return-path alignment, spam scores, source IP candidates and mail hops.
3. Run Network Checks
Test SMTP/IMAP/POP ports, email DNS records, SMTP capabilities and IP reputation using server-side native networking functions.
Upload .eml or text file or drag & drop here
For best results use “Show original”, “View source”, or “View raw message” in your mail client.
Email Header Analysis
Authentication & Delivery Findings
Mail Route / Received Hops
| # | Server / From | IP addresses | Date / Detail |
|---|
Checks SMTP 25/465/587/2525, IMAP 143/993, POP3 110/995 and ManageSieve 4190 using native PHP sockets.
Email Port Check
Checks selected DNS-based blocklists. Results depend on each list's access policy and your server resolver.
Spamhaus note: its public ZEN service is intentionally not bundled into this commercial public tool. Spamhaus states public DNSBL usage is free only for qualifying low-volume non-commercial use; a commercial deployment should use an appropriate Spamhaus service/DQS instead.
IP Blacklist Check
Checks MX, SPF, DMARC, TLS-RPT and an optional DKIM selector. Common selectors include selector1, selector2, google, default and vendor-specific names.
Email DNS & Authentication
Connects only long enough to read the banner and issue a fixed EHLO. It does not authenticate, send mail, relay mail, or accept user-supplied SMTP commands.
SMTP Banner & Capabilities