ToolsViewer's Email Viewer is a free html email preview tool for HTML and MJML email: live multi-client preview (Gmail, Outlook, Apple Mail, Yahoo), dark-mode simulation, merge-tag payloads, MJML compilation, CSS inlining, a pre-send QA report, and link checks — all in your browser, with no signup.
Paste HTML or MJML (compiled to email HTML in your browser), import a .html file, or open a gallery template. Preview desktop and mobile client profiles, use Add device to compare screens, toggle light / dark mode, and apply a sample JSON payload to substitute {{ merge tags }} in the preview.
Nothing is uploaded for editing or preview. View Detail opens rendered HTML, source, plain text, a QA report scored out of 100, HTML compatibility check, and a structural link check — without an SMTP server or account.
It does not open .eml or .msg files, and client previews are simulations (viewport + CSS quirk overrides), not native Gmail or Outlook engines. Confirm critical campaigns with real inbox tests when needed. For general webpage HTML (not email), use HTML Viewer Pro.
.html file, or switch to MJML and compile it.{{ variables }} in the preview.{{ tags }} without sending mailEmail Viewer is ToolsViewer’s free html email preview and editor for HTML and MJML in the browser. It includes client-style previews, dark-mode simulation, merge-tag payloads, CSS inlining, QA, and link checks — without uploading drafts or opening .eml/.msg files.
Yes. Core editing, preview, MJML compile, CSS inlining, QA, and export work without signup.
No. Editing, preview, MJML compilation, linting, link checks, the QA report, and HTML-to-text conversion all run locally in your browser.
No. Email Viewer works with HTML and MJML markup (paste, .html/.htm import, or templates) — not MIME email files.
You can preview client-style simulations for Gmail, Outlook, Apple Mail, Yahoo, or Standard on desktop or mobile, and use Add device to compare profiles. These are not native inbox engines — confirm critical campaigns with real tests when needed.
Yes. Toggle light/dark to simulate how each profile handles dark mode — for example Gmail-style inversion versus clients that keep designed colors.
Yes. Switch to MJML mode and markup is compiled to email-ready HTML in your browser. Click Get HTML to put the compiled output into the editor.
Yes. Open Payload, paste JSON (or use the template sample), check coverage, and Apply payload. Substitution updates the preview; your editor source keeps the tags.
Yes. Use Inline CSS to move supported style rules into style attributes, which helps with clients that strip style blocks.
It runs nine structural checks — Gmail clipping, unsubscribe link, image-only content, alt text, external stylesheets, DOCTYPE, structural tags, placeholder links, and viewport — and scores your email out of 100. You can save a PDF via your browser’s print dialog.
No. It flags common issues such as scripts, forms, unsupported CSS, relative links, missing alt text, and Gmail clipping risk — it cannot guarantee every inbox.
No. It performs structural checks only (empty, JavaScript, relative, mailto, tel, http, https, fragment) without CORS-prone HEAD requests.
Yes. The Text tab converts the HTML into a simple plain-text version with basic line breaks and decoded entities.
No. Optional drafts and preferences stay in local storage on your device.