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Spam Score
Paste your subject and HTML to get a SpamAssassin-style score with per-rule breakdown and fixes.
This tool is being wired up. The analyzer ships in the next build phase.
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.