Spam Score Checker
Paste a subject line and email body to get a 0 to 100 spam-risk score with an itemized breakdown: trigger words, ALL-CAPS, punctuation, links and content length. Free, no sign-up, runs in your browser.
Heuristic scan: about 110 trigger phrases plus formatting signals. Content is only one factor filters use. Sender reputation and SPF, DKIM and DMARC authentication matter more.
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How spam filters actually work
Modern spam filters are reputation systems first and content scanners second. Gmail, Outlook and Yahoo decide placement primarily from how recipients have treated your past mail: opens, replies, spam complaints, and deletes without reading. Authentication is the other heavyweight: SPF publishes which servers may send for your domain, DKIM cryptographically signs each message, and DMARC tells receivers what to do when those checks fail. Mail that fails authentication or comes from a domain with complaint history lands in junk no matter how clean the copy is. Content analysis still matters, especially for new senders with no reputation yet, which is where a tool like this one helps: it catches the obvious content signals before you hit send.
What this checker measures
The score combines six heuristic signals, each shown with its point weight in the breakdown:
- Trigger words and phrases: about 110 classics like free, guarantee, winner, cash, act now, limited time, risk free and congratulations. Subject-line triggers weigh more than body triggers.
- ALL-CAPS words: shouting is a hallmark of spam, and an all-caps subject is penalized extra.
- Exclamation marks: one is fine; several, and especially runs like !!!, add points fast.
- Suspicious symbols: sequences like $$$ that almost never appear in legitimate mail.
- Link density: a short email packed with links is a classic phishing pattern.
- Content length: extremely thin bodies with a link mimic image-only spam used to dodge text scanners.
Read the verdict bands as guidance, not verdicts from a real filter: under 25 looks clean, 25 to 59 needs review, 60 and above is high risk. Rewrite flagged phrases into plainer language, then retest.
Frequently asked questions
How is the spam score calculated?
The tool scans your subject and body for roughly 110 known spam-trigger words and phrases, then adds weighted points for ALL-CAPS words, exclamation marks, suspicious punctuation like $$$ and !!!, high link counts, and very thin content. The total is capped at 100 and mapped to three verdict bands: looks clean, needs review, high risk.
Does a low spam score guarantee inbox delivery?
No. Content is only one signal among many. Modern filters weigh sender reputation, engagement history, and authentication (SPF, DKIM, DMARC) far more heavily than word choice. A clean score here can still land in spam if your domain reputation is poor.
What are SPF, DKIM and DMARC?
They are email authentication standards set up in DNS. SPF lists the servers allowed to send for your domain, DKIM adds a cryptographic signature to each message, and DMARC tells receivers how to handle messages that fail the first two checks. Together they prove your mail is really from you.
Which words trigger spam filters most?
The classics: free, guarantee, winner, cash, act now, limited time, risk free, no obligation, 100%, click here, buy now, urgent and congratulations. One trigger word rarely dooms an email; stacking several in a short subject line is what pushes scores up.
Is my email text uploaded anywhere?
No. The scan runs entirely in your browser with inline JavaScript. Nothing you paste is transmitted or stored.