CHECK · COMPLY · IMPROVE
One-Click Unsubscribe Checker
Paste an email header to check one-click unsubscribe configuration, RFC 8058 evidence, provider readiness, and the next steps to improve it.
✓ Local header analysis · ✓ No sign-up required · ✓ Evidence-aware results · ✓ Clear next steps
List-Unsubscribe:<https://unsubscribe.example-mail.net/u/abc123>List-Unsubscribe-Post:List-Unsubscribe=One-ClickFrom:Example News <news@example.com>HTTPS URL and POST instruction detected.
One-Click Unsubscribe Workspace
Review the unsubscribe evidence found in your message header.
Overall Result
Your message header’s one-click unsubscribe readiness.
One-click unsubscribe is set up
The required RFC 8058 header structure is present. Endpoint behavior still requires separate verification.
Unsubscribe Checks
Eight checks based on the header evidence available to Mailvovo.
List-Unsubscribe header found
<https://unsubscribe.example-mail.net/u/abc123>, <mailto:unsubscribe@example.com?subject=unsubscribe>Configured for RFC 8058 one-click
List-Unsubscribe=One-ClickValid HTTPS unsubscribe URI
https://unsubscribe.example-mail.net/u/abc123Valid mailto fallback found
mailto:unsubscribe@example.com?subject=unsubscribeUnsubscribe header syntax parsed
2 unsubscribe methods detectedUnsubscribe host uses a different domain
unsubscribe.example-mail.netHeader-only analysis cannot verify a remote one-click POST response
Network verification not performedRequired one-click header evidence is present
HTTPS URI + List-Unsubscribe-PostDetected Unsubscribe Headers
Parsed directly from the email header you supplied.
<https://unsubscribe.example-mail.net/u/abc123>, <mailto:unsubscribe@example.com?subject=unsubscribe>List-Unsubscribe=One-Clickhttps://unsubscribe.example-mail.net/u/abc123mailto:unsubscribe@example.com?subject=unsubscribeAbout One-Click Unsubscribe
One-click unsubscribe lets recipients unsubscribe from eligible commercial email through standards-based message headers. Mailvovo checks the List-Unsubscribe and List-Unsubscribe-Post fields, available unsubscribe methods, header syntax, domain evidence, and provider readiness from the email header you supply.
What it checks
- List-Unsubscribe header
- List-Unsubscribe-Post
- HTTPS unsubscribe URI
- Optional mailto fallback
- Header syntax and formatting
- Unsubscribe host evidence
Who it’s for
- Email marketers
- E-commerce businesses
- Newsletter teams
- SaaS product teams
- Agencies and developers
- Anyone sending commercial email
Important to know
- Paste the complete original email header
- Headers are parsed locally in your browser
- One-click requires an HTTPS URI and POST header
- Third-party unsubscribe hosts can be legitimate
- Remote endpoint responses need separate evidence
- A ready header does not guarantee inbox placement
How It Works
Check one-click unsubscribe readiness in four simple steps.
- 1Paste Email Headers
Add the complete original header from a message.
- 2We Parse the Evidence
Mailvovo reads unsubscribe fields and related header details.
- 3Review Readiness
See what passes, needs attention, or still requires evidence.
- 4Fix & Recheck
Apply the recommendations and test another header.
Frequently Asked Questions
RFC 8058 describes a standards-based unsubscribe flow that lets participating mailbox providers send a single POST request to the HTTPS URL advertised in an email header.
The core structure is a List-Unsubscribe header containing a valid HTTPS URI and a List-Unsubscribe-Post header with List-Unsubscribe=One-Click.
This page parses the header locally. It deliberately does not make or simulate a cross-origin unsubscribe POST request, so it cannot confirm the live endpoint response.
No. A valid HTTPS URI and one-click POST instruction are the key evidence for RFC 8058. A mailto method is an optional fallback.
A different host can be a legitimate sending-platform domain, but a header alone cannot establish its ownership. Review it against your sending configuration.
No. Analysis runs locally in this page and does not require the header to be uploaded for parsing.
Check Another Email Header
Paste another message header to review its one-click unsubscribe configuration.