For the complete site index, see llms.txt. Docs index: llms-docs.txt. Marketing corpus: llms-full.txt. Docs corpus: llms-full-docs.txt. Prefer markdown URLs where available (append .md).. Product skill: skill.md. Pricing: pricing.md. Docs MCP: /docs/mcp. Site MCP: /mcp.

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Email Deliverability & Spam Tester

Send a test email from your ESP, SMTP server, or client to get a complete 0–10 deliverability report. Tests SPF, DKIM, DMARC alignment, reverse DNS, 40+ blocklists, Rspamd spam filters, and link reachability.

Step 1: Send Your Test Email

Send an email to this address

Copy this temporary inbox address into your ESP (or email client) and send your campaign.

Want to test without opening your mail client?

Comprehensive deliverability diagnostics.

Evaluate technical mail server compliance, cryptographic signatures, and spam filter heuristics before sending campaigns to real customers.

Full RFC Authentication

Verifies cryptographic DKIM signatures, SPF return-path authentication, strict DMARC alignment, and forward-confirmed reverse DNS (FCrDNS).

40+ Public DNS Blocklists

Queries sending IPs on Spamhaus ZEN, Barracuda, SpamCop, SEM, UCEPROTECT, and sender domains on Spamhaus DBL, URIBL, and SURBL.

Rspamd & Content Heuristics

Extracts live Rspamd spam symbols, score deductions, deceptive trigger keywords, and uppercase formatting penalties.

24-Hour Privacy Guarantee

Test sessions and MIME payloads are automatically deleted after 24 hours. No data is stored long-term or shared publicly.

Automate deliverability checks via API.

Integrate automated spam scoring into your CI/CD pipelines, staging environments, or internal email review workflows.

1

Install the Node.js package

npm install reloop-email
2

Test deliverability with Node.js

test_deliverability.ts
1import { Reloop } from "reloop-email";
2

3const client = new Reloop({
4  apiKey: process.env.RELOOP_API_KEY,
5});
6

7// 1. Create a temporary test inbox session
8const session = await client.tools.deliverability.createSession();
9console.log(`Send your test email to: ${session.address}`);
10

11// 2. Poll for incoming test results
12const report = await client.tools.deliverability.pollSession(session.token, {
13  timeoutMs: 30000,
14});
15

16console.log(`Deliverability score: ${report.score}/10 (${report.grade})`);
17console.log(`Verdict: ${report.verdictLabel}`);
3

Inspect JSON deliverability report (200 OK)

response.json
1{
2  "token": "test-8f3b2c1a",
3  "address": "test-8f3b2c1a@mail-test.reloop.email",
4  "status": "received",
5  "report": {
6    "score": 9.5,
7    "grade": "A+",
8    "verdict": "inbox_ready",
9    "verdictLabel": "Inbox Ready (Excellent)",
10    "summary": "Your email passed major authentication, blacklist, and content checks.",
11    "from": { "address": "sender@example.com", "domain": "example.com" },
12    "subject": "Your Monthly Report",
13    "categories": {
14      "signature": {
15        "id": "signature",
16        "title": "Authentication & Identity",
17        "mark": 0.0,
18        "status": "pass",
19        "items": [
20          { "id": "auth-spf", "title": "SPF", "mark": 0, "status": "pass" },
21          { "id": "auth-dkim", "title": "DKIM", "mark": 0, "status": "pass" },
22          { "id": "auth-dmarc", "title": "DMARC", "mark": 0, "status": "pass" }
23        ]
24      },
25      "blacklists": { "id": "blacklists", "mark": 0.0, "status": "pass" },
26      "content": { "id": "content", "mark": -0.5, "status": "warn" },
27      "body": { "id": "body", "mark": 0.0, "status": "pass" },
28      "links": { "id": "links", "mark": 0.0, "status": "pass" }
29    }
30  }
31}

Frequently asked questions.

Everything you need to know about technical deliverability, score calculation, privacy, and mail-tester parity.

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