Email spam checker for cold emails, scored on 1,116,744 first emails' replies
By Ryan Doyle, co-founder of Sales.co. Published October 24, 2026, updated October 24, 2026.
Paste a cold email for its spam trigger words and the reply rates of emails like it. Across 1,116,744 first emails Sales.co sent from Oct 6, 2025 to Oct 9, 2026, 8.8% had a trigger word and drew about as many human replies as emails with none (0.75% vs 0.69%). Urgency words went with fewer interested replies (14 of 12,933, 0.11% vs 0.20%). Exclamation marks went with fewer replies of both kinds (0.54% vs 0.70% human, 0.10% vs 0.20% interested).
For B2B founders and sales teams who write their own cold email. The check runs in your browser; nothing you paste is sent or stored.
What this page adds: each group of trigger words carries the human reply rate of the first emails that used it, from 1,116,744 emails and 7,720 human replies in one company's own sending. Each email was read once and turned into counts; no email text is published.
The five groups of trigger words
- Money and free-offer words ("100% free", "for free", "free trial", "free consultation", "free audit", "free gift" and more): 2.9% of first emails; 0.75% human replies with them against 0.69% without.
- Urgency words ("act now", "urgent", "limited time", "expires today", "expires soon", "hurry" and more): 1.2% of first emails; 0.60% human replies with them against 0.69% without.
- Hype and guarantee words ("guarantee", "guaranteed", "100%", "amazing", "incredible", "unbelievable" and more): 4.8% of first emails; 0.80% human replies with them against 0.69% without.
- Pushy calls to action ("click here", "click below", "click the link", "buy now", "order now", "sign up free" and more): 0.1% of first emails; too few to show a rate.
- Scam-style phrases ("dear friend", "this is not spam", "not spam", "no hidden fees", "no hidden costs", "congratulations" and more): 0.1% of first emails; too few to show a rate.
The full word list is in the table at the end of this page. Bare "free" is left out on purpose ("feel free to reply" is ordinary writing); free offers are in.
Every check and its reply rate
One row per value. An email counts once: it is the first email a prospect got from that sender, and a reply counts if any human reply came back from their address.
| Check | Value | First emails | Human reply rate | Interested rate | Human rate, largest sender removed |
|---|---|---|---|---|---|
| Trigger words in the body | None | 1,018,076 | 0.69% | 0.20% | 0.62% |
| 1 | 92,476 | 0.74% | 0.20% | 0.72% | |
| 2 | 5,837 | 0.87% | 0.09% | 0.88% | |
| 3 or more | 355 | not shown | not shown | not shown | |
| Money and free-offer words | Yes | 32,571 | 0.75% | 0.24% | 0.65% |
| No | 1,084,173 | 0.69% | 0.19% | 0.63% | |
| Urgency words | Yes | 12,933 | 0.60% | 0.11% | 0.60% |
| No | 1,103,811 | 0.69% | 0.20% | 0.63% | |
| Hype and guarantee words | Yes | 53,409 | 0.80% | 0.18% | 0.83% |
| No | 1,063,335 | 0.69% | 0.20% | 0.62% | |
| Pushy calls to action | Yes | 1,269 | not shown | not shown | not shown |
| No | 1,115,475 | 0.69% | 0.20% | 0.63% | |
| Scam-style phrases | Yes | 996 | not shown | not shown | not shown |
| No | 1,115,748 | 0.69% | 0.20% | 0.63% | |
| ALL-CAPS words | None | 980,087 | 0.70% | 0.20% | 0.63% |
| 1 to 2 | 131,734 | 0.63% | 0.16% | 0.62% | |
| 3 or more | 4,923 | not shown | not shown | not shown | |
| A link in the first email | Yes | 2,201 | 0.64% | 0.05% | 0.64% |
| No | 1,114,543 | 0.69% | 0.20% | 0.63% | |
| An exclamation mark | Yes | 35,192 | 0.54% | 0.10% | 0.54% |
| No | 1,081,552 | 0.70% | 0.20% | 0.63% | |
| Body length | 1 to 25 words | 1,495 | not shown | not shown | not shown |
| 26 to 50 words | 81,656 | 0.76% | 0.24% | 0.66% | |
| 51 to 75 words | 394,996 | 0.71% | 0.22% | 0.62% | |
| 76 to 100 words | 412,039 | 0.68% | 0.18% | 0.61% | |
| 101 to 125 words | 163,133 | 0.66% | 0.17% | 0.68% | |
| 126 to 150 words | 54,443 | not shown | not shown | 0.67% | |
| 151 or more words | 8,982 | not shown | not shown | 0.76% |
All first emails: 0.69% human replies, 0.20% interested (largest sender removed: 0.63%). Link, exclamation and length rows come from the body read of 1,116,744 first emails (data through October 9, 2026). "Not shown": fewer than 2,000 emails, or one sending workspace made more than 45% of them. Source: Sales.co sending data, October 6, 2025 to October 9, 2026.
Limits of this data
The strongest objection: a reply rate mixes two things, whether the email reached the inbox and whether the reader wanted to answer, and this data cannot split them. It also travels with the list and the offer: a sender who writes "guaranteed" may also pick looser lists. These are associations across 57 sending workspaces, so use the checker to find words worth cutting, then test on your own list. The subject line is not part of this read; the subject line grader covers it.
What to do with this
Cut urgency words first: they went with fewer human and interested replies (0.60% vs 0.69% human, 14 interested replies of 12,933 emails). Emails with two trigger words drew 0.09% interested replies against 0.20% (5 interested replies of 5,837 emails, too few to be sure), so test any limit on your own list. Drop exclamation marks (0.54% vs 0.70%). Write acronyms and names in normal case, and keep the first email plain. Then check the setup no text checker sees: SPF, DKIM and DMARC on the sending domain, warmed mailboxes and a clean list (the cold email deliverability guide walks through it). For what to write instead, see cold email best practices tested on our sends.
If you would rather have someone write and send it, Sales.co runs done-for-you cold email from $2,000 a month for up to 10,000 emails, month-to-month. See pricing.
Method
- Source: Sales.co's sending database, the text of each cold email sent and the replies the sending tool labeled. Unit: recipient thread: one recipient address in one sending workspace, described by the first email that address got; 1,116,744 of them, October 6, 2025 to October 9, 2026.
- A human reply means the prospect replied at least once with a reply that is not an auto-reply, out-of-office, bounce, warm-up, test or spam (sending tool's labels). An interested reply means at least one of those replies was labeled 'possibly interested'.
- Trigger words: phrases from the five trigger-word groups in the word list below found in the email body (subject not included). A phrase counts once per place it appears; longer phrases win over the shorter ones inside them. All-caps words: all-caps words of four or more letters, leaving out common business acronyms.
- A reply counts only when it came from the address that was emailed, so every rate here is a floor. Left out: any value with fewer than 2,000 emails, or where one sending workspace made more than 45% of them. The largest sender made 16% of all first emails, so the table also shows each rate with it removed. No client is named and no email or address is published.
- Refresh: each time the data is recomputed, this page is regenerated from it; the freshness line at the top is written from the data file.
Cite this: Sales.co, "Email spam checker for cold email", https://sales.co/email-spam-checker, data through October 9, 2026.
The full trigger word list
Money and free-offer words: 100% free, for free, free trial, free consultation, free audit, free gift, free access, free offer, free quote, free sample, risk free, no cost, at no cost, fast cash, cash bonus, earn money, make money, extra income, save big, big savings, lowest price, best price, cheap, discount, double your, financial freedom, million dollars, $$$, prize, winner, bonus, cost nothing.
Urgency words: act now, urgent, limited time, expires today, expires soon, hurry, don't miss out, dont miss out, last chance, only a few left, today only, immediately, now or never, offer ends, before it's too late, while supplies last, time is running out, final notice.
Hype and guarantee words: guarantee, guaranteed, 100%, amazing, incredible, unbelievable, miracle, revolutionary, once in a lifetime, no risk, no catch, no obligation, no strings attached, best ever, life-changing, game changer, game-changer, skyrocket, explode your, 10x your.
Pushy calls to action: click here, click below, click the link, buy now, order now, sign up free, apply now, call now, visit our website, special promotion, exclusive deal, exclusive offer, limited offer, act fast, don't delete, do not delete.
Scam-style phrases: dear friend, this is not spam, not spam, no hidden fees, no hidden costs, congratulations, you have been selected, you've been selected, verify your account, account suspended, casino, weight loss, lose weight, viagra, crypto opportunity, wire transfer.
Where to go next
subject line grader · cold email best practices · cold email deliverability · cold email statistics · all Sales.co research
Sources
- Sales.co sending database: 1,116,744 first emails and 7,720 human replies, October 6, 2025 to October 9, 2026, as of October 24, 2026.
- Sales.co pricing and plans: sales.co/pricing, read October 24, 2026.
FAQ
What are spam trigger words?
Words and phrases that spam filters and readers link with junk mail: free offers and money talk ("free trial", "lowest price"), urgency ("act now", "limited time"), hype ("guaranteed", "100%"), pushy calls ("click here", "buy now") and scam-style lines ("dear friend", "this is not spam"). The checker flags 102 of them in five groups.
Do spam trigger words hurt cold email replies?
Not the number of replies, in Sales.co's data. First emails with no trigger words got 0.69% human replies; those with one or more got 0.75%. Emails with two trigger words drew 0.09% interested replies against 0.20% with none (5 interested replies of 5,837 emails, too few to be sure). Urgency words went with fewer interested replies (14 of 12,933 emails, 0.11% vs 0.20%). The group that went with fewer human replies in both cuts: urgency words (78 replies, a small group). Hype and guarantee words went with more (0.80% vs 0.69%); the limits section below says why that is no reason to add them.
Is "free" a spam word?
On its own, no: "feel free to reply" is ordinary writing, so the checker does not flag the bare word. It flags free offers such as "free trial", "for free", "free audit" and "100% free", which read as a pitch.
Should a cold email have a link?
First emails with a link got 0.64% human replies against 0.69% without one, across 1,116,744 first emails. Only 2,201 had a link (14 human replies), too few to call a difference. A link also gives a filter one more thing to score, so many senders keep the first email plain and send the link after a reply.
Do ALL-CAPS words or exclamation marks hurt?
Emails with one or two all-caps words (acronyms left out) got 0.63% human replies against 0.70% with none. An exclamation mark went with 0.54% against 0.70% without.
What else sends cold email to spam?
Mostly things no text checker can see: a sending domain without SPF, DKIM and DMARC, a new domain sending too much too soon, a list with many bad addresses, and recipients marking you as spam. Fix those first; the words matter less than the setup. See the cold email deliverability guide linked below.