About this tool
Audit email HTML for client compatibility, accessibility, spam risk and performance with a live preview and deterministic rule-based scoring.
HTML Email Checker is a free marketing & social tool that runs entirely in your browser — nothing to install, no account to create, and your data never leaves your device. Open the page, add your input, and get a clean, copy-ready result in seconds.
Open HTML Email Checker on AltFTool — it loads instantly in your browser.
Paste your code or data sample into the workspace.
Pick the format, conversion, or analysis you need.
Copy the polished result straight back into your project.
Paste snippets, payloads, or commands straight from your editor and get a tidy, shareable result in one step.
Format, convert, or inspect data before it lands in tests, documentation, or production requests.
Use the generated output as a copy-ready starting point instead of writing everything by hand.
Yes — HTML Email Checker is completely free on AltFTool, with no signup, no trial limits, and no hidden costs.
Yes. HTML Email Checker runs in your browser, so what you enter or upload stays on your device instead of being sent to a server.
Audit email HTML for client compatibility, accessibility, spam risk and performance with a live preview and deterministic rule-based scoring. It's built for quick, everyday marketing & social tasks with results you can copy or download straight away.
Yes — HTML Email Checker works in any modern browser, on desktop, tablet, and mobile, with the same features everywhere.