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Spam Score
Paste your subject and HTML to get a SpamAssassin-style score with per-rule breakdown and fixes.
About this check
Score subject and HTML for spam triggers.
Frequently asked questions
- What does the Spam Score actually check?
- Score subject and HTML for spam triggers.
- Is this really free?
- Yes. Every on.bo tool is free, no signup required, no rate-limit tricks.
- Do you store the data I check?
- We log minimal metadata to keep the service healthy. Lookups themselves are not retained beyond short-term caching.