Spam score: what a checker can tell you, and what Gmail decides
A tester's guess at whether your email looks like spam. Handy for catching a broken setup. No use at predicting where Gmail puts next Thursday's campaign.
- 125Spam Score
- A score that predicts the likelihood of an email being marked as spam, influenced by content and sender reputation.
- Comes from
- Testing tools that run your email past rule-based filters before you send
- Not the same as
- Where Gmail or Outlook actually files your email for real subscribers
- Matters more
- Spam complaints, bounces and authentication, watched over weeks
A spam score is a tester's guess, not the inbox's verdict
Here's the hard truth: Gmail doesn't give you a spam score, and no mailbox provider publishes how it decides. The number you've seen comes from a testing tool that runs your email past a set of rules, adds points for anything suspicious, and tells you whether you crossed its line. Rule-based filters like the open source SpamAssassin work that way.
That's useful, up to a point. The rules can see your content, your links and your authentication. They can't see whether your subscribers open you, ignore you or report you, and that history weighs heavily with the big inboxes.
What a spam checker catches that's worth fixing
- SPF, DKIM and DMARC missing, failing, or not aligned with your from address
- An email that's one big image with hardly any text
- Link shorteners, and links to domains with a poor name
- Broken or bloated code pasted in from a design tool
- A sending or link domain sitting on a public blocklist
Those are real faults, and a checker finds them in minutes. Klaviyo's help centre suggests test sends and outside tools for exactly this, adding the email back piece by piece if something keeps landing in spam.
Some of what a checker docks points for is cosmetic: a shouty subject line, the word free. Gmail is judging far more than vocabulary, so don't wreck a good email to please a tester.
The signals that decide where your email lands
Mailbox providers judge the sender over weeks: complaints, bounces, engagement, how steady the volume is. Google Postmaster Tools shows the spam rate Gmail users report against your domain. It's the closest thing to an official spam score you'll get.
| Signal | Where to see it |
|---|---|
| Spam complaints | Google Postmaster Tools, once your domain is verified there |
| Bounces | Every campaign and flow report in Klaviyo |
| Authentication | The headers of a real send, opened in Gmail |
| Engagement | Clicks and orders per send to the same segment, over time |
If those are healthy, a middling checker score won't hurt you. If they're not, a perfect one won't save you. Our post on why emails go to spam works through them in the order we check.
Related terms
FAQs
What spam score should I aim for?
Whatever the tool calls a pass, and then stop. Testers use different scales and different rules, so there's no universal number worth chasing. Fix every real fault it names, ignore the cosmetic ones, and spend the time you saved on your complaint rate and your list.
Can an email with a good spam score still land in spam?
Yes. A checker sees one email on its own. Gmail sees months of how your subscribers treated your mail, and a list full of people who never open can drag a perfectly built email into spam. Fix the audience and the sending pattern first.
Do spam trigger words still matter?
Much less than the internet says. A tester may dock points for words like free or a subject line in capitals, but the big inboxes lean on reputation and how readers react. Write like a person talking to a person, use a from name people recognise, and the words take care of themselves.
Rather we explained it on your own account?
Bring your Klaviyo account to a growth consultation. We'll walk through what this means for your numbers, in plain English, and what we'd fix first.
Half an hour with Theo, our founder.
We're all about relationships built on trust, mutual respect and a shared vision for success. If that sounds like your vibe, let's make some waves together 🌊
