Email Tools

Three tools for getting an email right before you hit send: a subject line tester, a spam-word checker and an HTML signature generator. No account and no mailing-list signup — paste, check, fix.

Test subject lines and spam risk before sending

The Email Subject Line Tester scores a subject on the mechanical factors that correlate with opens: length in characters and words — mobile clients truncate somewhere around 40 characters — plus spam trigger phrases, all-caps runs and excess punctuation. No tool can guarantee an open rate, but this one catches the avoidable mistakes, like a subject that gets cut off exactly where the offer was, before a campaign goes out to a full list rather than after.

The Email Spam Checker scans your complete email copy for the trigger words and patterns filters weigh against you — “act now”, “100% free”, strings of exclamation marks. Modern spam filtering looks at far more than word lists, but flagged phrases still add up, and rewriting a handful of them is the cheapest deliverability improvement available. The check runs in your browser, so an unannounced product launch or a sensitive internal memo is not passed through a third-party analysis service on its way to being checked.

Generate a signature that survives email clients

The Email Signature Generator builds a clean HTML signature — name, role, company, phone, links — that renders correctly in Gmail and Outlook. That is harder than it sounds: email clients ignore most modern CSS, so a signature has to be constructed from the small, old-fashioned subset of HTML they all still respect. Fill in your details, copy the result, and paste it into your mail client’s signature settings once; every message after that carries it automatically.

Frequently asked questions

Can any tool guarantee my email avoids the spam folder?

No — and be wary of one that claims to. Filters weigh sender reputation, authentication (SPF, DKIM, DMARC), engagement history and content together. What the Email Spam Checker does is remove the content-level risks you control, which is one real factor among several.

How long should an email subject line be?

Aim for roughly 30 to 45 characters. Mobile clients truncate around the 40-character mark and desktop clients not much later, so front-load the words that matter. The Email Subject Line Tester measures your subject and flags it when the important part is likely to be cut off.

Will the generated signature work in both Gmail and Outlook?

Yes — that pair is exactly what the Email Signature Generator targets. It uses only the conservative HTML that both clients render reliably, avoiding the modern CSS features that Outlook in particular strips out. Paste it into your client’s signature settings and send yourself a test message to confirm.

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