Your Domain Has Gaps. These Tools Find Them.
38 free tools for eCommerce brands, email marketers, and agencies to diagnose, fix, and protect their email deliverability — no account needed.
Why These Tools Exist
Email deliverability requires constant vigilance. SPF, DKIM, and DMARC configurations drift. Domains land on blacklists. List quality degrades silently. Authentication records break after server migrations. These tools exist to catch those problems instantly — no account needed, no software to install — so you can fix them before they destroy your sender reputation.
InboxEagle monitors these signals automatically for 2,000+ brands, tracking 248M+ emails per month. These free tools give everyone the same visibility into their domain health and authentication posture — so you can understand what's broken and take action immediately.
Domain Scanner
See your full email security posture in 30 seconds — every authentication record, MX config, and security layer graded in one scan.
Email Deliverability Health Check
Find out why your emails are landing in spam. Get an instant A–F grade on SPF, DKIM, DMARC, and blacklist status — with plain-English fixes.
DMARC Record Checker
Without DMARC, anyone can spoof your domain. Instantly see if your DMARC policy is enforcing, monitoring-only, or missing — with a fix plan.
SPF Record Checker
A broken SPF record silently kills deliverability. Validate yours in seconds — see every mechanism, count DNS lookups, and catch the errors causing rejections.
DKIM Record Checker
DKIM failure is the #1 cause of Gmail spam placement. Look up your signing key, verify it's valid, and catch weak or revoked keys before they cost you.
BIMI Record Checker
Is your brand logo actually showing in Gmail and Apple Mail? Validate your BIMI record and VMC certificate in one lookup.
MTA-STS Record Checker
Check whether your inbound email delivery is protected by TLS encryption — and find out if your MTA-STS policy file is reachable.
TLS-RPT Record Checker
Verify your domain is configured to receive TLS delivery failure reports — so TLS encryption problems surface before they block your mail.
Email Blacklist Checker
A single blacklist listing can block emails at Gmail, Outlook, and Yahoo. Check your domain and sending IP across 50+ blacklists — get severity ratings and delisting steps.
Email Header Analyzer
When a specific email went to spam, the headers explain exactly why. Paste them here to see every hop, authentication result, and the point where delivery failed.
DNS Record Lookup
Query any DNS record type — A, MX, TXT, CNAME, NS — instantly. Useful for verifying published authentication records and diagnosing propagation delays.
Reverse DNS Lookup
Check if your sending IP has a valid PTR record and passes FCrDNS validation — the two-way DNS check ISPs use to block spam servers.
Email Spam Score Tester
Before your next campaign hits send, test it. Get a 0–10 spam risk score across authentication, SpamAssassin rules, blacklists, and content flags — catch issues first.
DMARC Record Generator
Generate a valid DMARC TXT record in 60 seconds — choose your enforcement policy, set up reporting, and get the exact DNS record to publish.
SPF Record Builder
Running Klaviyo, SendGrid, or Google Workspace? Select your ESPs and get a valid SPF record — with a lookup count warning so you don't hit the 10-mechanism limit.
DKIM Record Generator
Generate a DKIM TXT record with the right selector and key format — plus step-by-step instructions for publishing it in your DNS.
BIMI Record Generator
Create the BIMI TXT record that enables your logo in Gmail and Apple Mail inboxes — configure your SVG logo URL and optional VMC certificate.
MTA-STS Record & Policy Generator
Generate the MTA-STS DNS record AND the policy file content — everything you need to enforce TLS encryption for all email delivered to your domain.
TLS-RPT Record Generator
Create the TLS-RPT DNS record to start receiving automated TLS delivery failure reports — configure your reporting email or HTTPS endpoint.
Gmail Annotation Builder
Generate Gmail Promotions tab annotation code (JSON-LD + microdata) for deal badges, promo codes, and product carousels — with a live inbox preview.
Mailto Link Generator
Build a mailto: link with pre-filled To, CC, BCC, subject, and body — get a raw URL, HTML anchor, or styled button ready to paste anywhere.
List-Unsubscribe Header Generator
Generate RFC 2369 + RFC 8058 compliant List-Unsubscribe headers for Google and Yahoo 2024 bulk sender requirements. Includes code for PHPMailer, Nodemailer, and Python.
Email Subject Line Analyzer
Score your subject line for length, spam signals, personalization, emojis, and engagement patterns. Get an instant 0–100 score with ranked fixes.
Email Signature Generator
Build a professional HTML email signature with inline CSS — compatible with Gmail, Outlook, and Apple Mail. Live preview, 3 templates, instant HTML export.
Email Plain Text Generator
Convert your HTML email to a clean, deliverability-safe plain-text version. Every HTML campaign should include a text/plain MIME part — this generates it instantly.
Email Revenue Loss Calculator
Enter your send volume, open rate, and AOV — see exactly how much revenue is vanishing into the spam folder every month and what fixing it is worth.
Email Deliverability Score Calculator
Not sure where your deliverability actually stands? Answer 10 questions and get a 0–100 health score — with a ranked list of what to fix first.
Email Warm-Up Plan Generator
Sending from a new IP or domain? Generate a custom day-by-day warm-up schedule — volume ramps, engagement targets, and warning signs to watch for.
Email Spam Word Checker
Subject lines with spam trigger words get filtered before anyone sees them. Paste yours here — see exactly which words are flagging spam filters and what to replace them with.
Email List Health Estimator
Your unengaged subscribers are hurting your sender reputation and inflating your ESP bill. Calculate the exact contacts to cut and the monthly savings from cleaning.
Email Bounce Rate Calculator
Enter hard and soft bounce counts to see your bounce rates against Gmail and Yahoo thresholds — with safe, warning, and critical status for each.
Email Open Rate Calculator
Calculate your open rate and compare it against industry benchmarks for E-commerce, B2B SaaS, Agency, Nonprofit, and Media.
Spam Complaint Rate Calculator
Calculate your complaint rate and see exactly where it falls against Gmail's 0.08% deferral and 0.30% blocking thresholds.
Email Preheader Optimizer
Check length, detect spam words, count emojis, and see a live inbox simulation across Gmail Desktop, iOS Mail, and Gmail Mobile.
EML to HTML Converter
Upload any .eml file to extract and render the HTML body, view parsed headers, and download raw HTML. Runs in your browser.
Email Marketing Checklist
Running through 40 critical checks before every campaign? This interactive list covers authentication, list hygiene, content, testing, and compliance — progress saves as you go.
Cold Email Checklist
Cold email lives and dies on setup. Run through 40 checks covering domain warm-up, authentication, copy, follow-up cadence, and CAN-SPAM compliance before your first send.
These Tools Find the Problem. InboxEagle Prevents It.
Manual checks show you what's wrong today. InboxEagle monitors your domain 24/7 — authentication records, blacklist status, inbox placement across Gmail, Outlook, and Yahoo — and alerts you the moment something breaks. 2,000+ brands trust it to protect $248M in emails sent every month.
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