Email Accessibility Checker
See every accessibility issue, right in the email you're building.
43 curated axe-core rules plus 6 email-specific checks, run against the actual rendered email — not a generic page scan. Free, no signup.
👋 Free, no signup — part of the free Email Readiness score
How it works
Real rendering, not a static scan.
axe-core runs inside a hidden, rendered iframe against your actual email — not a text-only parse. That's what makes checks like colour contrast possible: they need real computed styles, which a static HTML scan can't provide.
43 curated axe-core rules cover images, links, ARIA, forms, and document structure — plus 6 checks axe doesn't run at all, written specifically for email: justified text, undersized fonts, missing preview text, generic link text, filename-as-alt-text, and layout tables missing role="presentation".
Findings are grouped Critical / Serious / Moderate / Minor — axe's own impact scale — with plain-English, email-specific copy instead of the generic web wording axe ships with by default.
Coverage
49 checks, six categories.
43 axe-core rules plus 6 email-specific checks marked with an asterisk — axe doesn't run those at all.
image-altinput-image-altarea-altalt-text-quality*
link-namebutton-namelink-in-text-blocklink-descriptive*
aria-valid-attr(-value)aria-required-attr / -children / -parentlist / listitempage-has-heading-one
labelselect-nameautocomplete-validform-field-multiple-labels
document-titlehtml-has-langhtml-lang-validvalid-lang
justified-textfont-size-minpreview-text-missinglayout-table-role
Document-level rules that actually mean something
Rules like document-title and html-has-lang need a real <html lang>/<title> to check against — MailViewr builds those from the Language and Title you set under Global Style → Document, the same values the real export and send-time HTML actually carry. The check runs against what will ship, not a fiction.
FAQ
Questions, answered.
Yes — free with no signup. It's one of two Email Readiness checks (along with the manual test-send) that don't require an account; Compatibility, Spam, and QA are free with a free account.
They're axe-core's own impact scale, used as-is: Critical and Serious findings typically block a screen reader user outright (missing alt text, no accessible name); Moderate and Minor are real but lower-impact issues (justified text, a generic-sounding alt attribute).
No automated tool can guarantee full compliance. This checker runs a curated, programmatically-detectable rule set — contrast ratios, missing alt text, invalid ARIA, and similar — but some WCAG success criteria (like whether alt text is actually meaningful) still need human judgment.
Email clients don't support native <video> playback, so MailViewr's video blocks render as a linked image instead — axe's video-caption rule checks for real <video> elements, which never appear in email output, so it's flagged as not applicable rather than silently skipped.
Build it. Check it. Make it readable.
Open the Email Builder and see a full accessibility report on the very first email you touch — no signup required.