Cold email checker

Paste the subject and the body. Each finding says whether it comes from a published rule, with the source and the date we read it, or is only our judgement. Nothing is sent anywhere, and there is no score.

What it checks, and where each rule comes from

Published rules: a subject that starts with Re: or Fwd: on a first email (CAN-SPAM, 15 U.S.C. § 7704(a)(2); Gmail's sender guidelines); no visible way to opt out and no postal address, when your tool does not add them (§ 7704(a)(5)); HTML that hides content, and links whose destination is hidden by a shortener (Gmail's guidelines). Our judgement, marked as such: merge fields left in the text, a missing or very long subject, all capitals, repeated exclamation marks, an emoji, several links, a long body, no question, a mentioned attachment. The sources were read on 2026-10-30; the page says which one each finding cites.

What it deliberately does not do

It gives no spam score and does not predict inbox placement. Gmail and Yahoo publish requirements on authentication, unsubscribe handling and complaint rates (spam rate under 0.30%), not a list of banned words, so a score built from word lists would be invented. Whether a message lands depends on your domain's SPF, DKIM and DMARC, your sending history and the recipient's own filters. Check the first with the SPF, DKIM and DMARC checkers on this site.

Why the footer matters more than the wording

Two of the three things CAN-SPAM asks for in every commercial email are in the footer: a way to opt out and the sender's postal address. GrowFast refuses to send until the account has saved a postal address, and puts a one-click unsubscribe link and header on every email, including follow-ups. If you send from another tool, tick the box above only if that tool really does the same.

Other checks

SPF record checkerReads the live SPF record, resolves every include it points at, and counts the DNS lookups. Over ten, receivers stop evaluating your SPF entirely.
DMARC record checkerReads the record at _dmarc on your domain and explains the policy it publishes — including the cases where a record exists but does nothing.
MX lookupResolves the MX records and names the provider behind them — which decides whether an address on this domain can be checked before you send to it.
DKIM record checkerFinds the DKIM key at <selector>._domainkey on your domain and reads its length and flags. Enter your selector if you know it; otherwise it tries the selectors the common providers use.
Cold email deliverability auditEvery DNS check on this site at once, for a domain you are about to send from. It takes about a second and touches nothing but DNS.

Cold email checker

What it checks, and where each rule comes from

What it deliberately does not do

Why the footer matters more than the wording

Other checks

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