Paste the exact subject and body. The tool checks language, capitalization, punctuation, links, merge tokens, template signals, and length, then explains the heuristic result.
Runs entirely in your browser. Your draft never leaves this page.
Paste the draft as it would send, with merge tokens filled in. This is a heuristic, not a placement guarantee.
Plain text is fine. If your tool sends HTML, paste the visible text.
Heuristic checks, not a guarantee. Real deliverability also depends on your domain and sender reputation - check those with the Domain Health Report.
Start typing and the read appears here: an overall score, the stats that drive it, and every finding with the exact fix.
Every number this tool shows, and where it comes from.
Spam-trigger lexicon. A curated list of 50+ phrases that appear in published filter rulesets and sender guidelines (Apache SpamAssassin rules, mailbox-provider bulk-sender documentation). Subject-line hits are weighted heavier than body hits, matching how filters score. References: Google bulk sender guidelines, Yahoo sender best practices.
Template and AI tells. Phrases like “I hope this email finds you well” arrive in millions of sends a day. Filters pattern-match them, and so do recipients. The list is the same one Orbit’s own outreach guardrails scrub against.
Length bands. 30-50 subject characters and 50-125 body words are the ranges that consistently correlate with reply rate in published cold-outreach benchmarks. Long messages get skimmed; one-liners look lazy or image-only.
Scoring. Start at 100; each red finding costs 14, each amber 6. The bands (85+ clean, 65-84 fixable, below 65 likely filtered) are opinionated but consistent - use the score to compare drafts, not as an absolute truth.
What it cannot see. Your domain’s SPF/DKIM/DMARC, sender reputation, list quality, volume ramp, and engagement history - which together matter more than copy. This tool covers the half you can fix in the editor.
Lexicons last reviewed 2026-07-03.
The rest of the toolkit runs in your browser too.
The other half of deliverability: SPF, DKIM, DMARC, MX, and registration checks on your sending domain.
Open the toolThe same honesty for DMs: platform-aware scoring for Reddit, LinkedIn, X, and Instagram openers.
Open the toolBrowse the rest of the free toolkit.
Open the toolOrbit can draft from account signals, apply guardrails, and stage the message for review before it sends.
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