Email Spam Words Checker
Test your email subject line, copy, and links in real time to avoid spam filters and land in the primary inbox.
Email Spam Words Checker
Check Spam score from code
Call the public spam check endpoint from your email pipeline or CI/CD. Analyze subject lines, trigger words, and deliverability metrics with a single request.
curl -X POST https://reloop.sh/api/tools/v1/spam-check \
-H "Content-Type: application/json" \
-d '{
"subject": "Your monthly analytics report is ready",
"body": "Hi Alex, your weekly metrics report has been generated. View your analytics dashboard online: https://reloop.sh/analytics"
}'Easily connect with your AI agents
Connect Reloop to any AI agent or MCP client in minutes.
MCP Server
1# Connect Claude to Reloop2claude mcp add reloop \3 -e RELOOP_API_KEY=rl_xxx \4 -- npx -y reloop-mcpConnect Claude Desktop, Cursor, or OpenClaw directly to Reloop. Auto-discovered tools for send, status & logs with zero glue code.
Developer CLI
1# Send transactional email2reloop emails send \3 --to user@example.com \4 --jsonDeterministic CLI for humans and agents. Built with machine-readable JSON output, stdin piping, and live webhook streaming.
Agent Skills
1# Install CLI agent skill2npx skills add \3 reloop/reloop-skills \4 --globalEquip Cursor, Claude Code, and autonomous agents with domain knowledge on Reloop templates, batching, and deliverability.
Frequently asked questions
Spam Score & Deliverability
An email spam score is a numerical rating calculated by spam filters (such as SpamAssassin, Gmail AI, or Microsoft Defender) evaluating how likely an email is to be unsolicited or malicious. Scores are based on content keywords, link density, formatting, and domain authentication (SPF, DKIM, DMARC).
Reloop's Spam Score Checker calculates a 0–100 score across 4 key dimensions: Subject Line Health (25 pts), Content & Trigger Words (35 pts), Link Safety & URL Shorteners (20 pts), and Formatting & Capitalization (20 pts). A score of 90+ means your email is inbox-ready.
Common spam words include artificial urgency phrases ('Act now', 'Limited time only'), aggressive financial promises ('100% free', 'Make money fast', 'Risk-free guarantee'), and clickbait terms ('Click here', 'Winner', 'Claim your reward'). Replacing these with natural phrasing prevents spam flags.
Best Practices & Troubleshooting
Spam filters heavily penalize generic URL shorteners because spammers use them to disguise phishing domains. Always use full, direct links with HTTPS or branded tracking subdomains connected to your verified sending domain.
Subject lines between 30 and 50 characters achieve the highest open rates and render properly on mobile screens. Subject lines over 70 characters are clipped by mobile clients, while ALL-CAPS or repeated exclamation marks (!!!) directly trigger spam penalties.
No. Content is one half of deliverability; the other half is technical authentication. You must also configure SPF, DKIM, and DMARC records on your domain. Reloop provides open-source email infrastructure with automated DKIM signing and deliverability monitoring.
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