Free Cold Email Spam Checker

A cold email spam checker analyzes your message before you hit send and scores how likely it is to land in the inbox versus the spam folder. Paste your subject line and body, and the tool scans for the things spam filters punish: trigger words (free, guarantee, act now, limited time), excessive punctuation and ALL-CAPS, too many links, urgency and money language, weak openers, and structural red flags.

You get a 0-100 deliverability score, a letter grade, and a specific fix for every issue it finds.

Why outbound teams test copy first: spam filters at Google and Microsoft read your content and compare it against patterns from billions of flagged messages. A single spammy subject line can route an otherwise good campaign straight to junk, where it gets zero replies and silently drags down your sender reputation.

Catching the triggers before you send is far cheaper than burning a domain.

The part a content checker can't fix: clean copy is necessary but not sufficient. The single biggest deliverability killer in cold outreach is not your words, it's your LIST. Sending to invalid, outdated, or spam-trap addresses produces bounces, and bounce rate is the metric mailbox providers weigh most heavily when deciding whether you're a spammer.

You can write a perfect email and still get blacklisted if 15% of your list is dead. Industry studies put B2B contact list decay at roughly 22-30% per year, so a list that was clean six months ago is already a liability.

This is where the spam checker hands off to Cleanlist. The tool above cleans your copy; Cleanlist cleans your list. Cleanlist's email verification checks every address across 15+ providers at 98% accuracy before you send, so your bounce rate stays under 2% and your domain reputation stays intact. Pair a verified list with inbox-safe copy and you protect the asset that every cold campaign depends on.

For sending-domain checks, also run the email blacklist checker to confirm your domain isn't already flagged. Privacy note: this tool analyzes your text locally in your browser. It does not store, send, or transmit your email content.

Spam filters at Google and Microsoft read every message and compare it against patterns from billions of flagged emails, then assign it a score. This checker approximates that logic against the signals filters weigh most: trigger words (free, guarantee, act now), urgency and money language, ALL-CAPS and excessive punctuation, link density, weak openers, and length.

Each signal adds risk, and the tool rolls them into a 0-100 deliverability score and a letter grade. A high score does not guarantee a filter will junk you, it means you are carrying avoidable risk that is cheap to remove before you send.

Work down the flagged list from the biggest offenders. Swap trigger words for plain language ("free trial" becomes "try it", "act now" becomes "this week"), cut exclamation points and ALL-CAPS, and keep links to one or two. Lead with a specific, human first line instead of "Dear Sir/Madam", and keep the email short.

Then fix what copy cannot: your list. The single biggest deliverability factor is bounce rate, so verify addresses with the free email verifier before you send, and confirm your domain is not flagged with the email blacklist checker. For the full playbook, see how to reduce email bounce rate.