RFC 5322 Compliant RegEx validation.
Disposable Email Checker
Enterprise-grade email validation tool. Detects burner domains, validates MX records via DNS over HTTPS, and analyzes username entropy to block bots and fraud.
Checks Syntax, MX Records, Domain Reputation, and Username Entropy.
Analysis Logic
-
⚙Syntax Engine
-
🔒Blacklist DB
Checks against 2,500+ known disposable domains.
-
🌐MX Lookup
Live DNS over HTTPS query to Google DNS.
-
🧪Entropy Check
Detects random strings like 'a83_z9'.
About
In the digital ecosystem, data hygiene is paramount. Temporary or "burner" email addresses - often provided by services like Mailinator or GuerillaMail - are primary vectors for spam bots, fraudulent sign-ups, and trial abuse. For marketers and system administrators, accepting these addresses damages sender reputation and skews analytics.
This tool utilizes a multi-layered verification protocol. Beyond simple syntax validation (Regex), it performs a live DNS lookup to verify MX records, ensuring the domain can actually receive mail. Crucially, it employs a Shannon Entropy algorithm to analyze the local part of the email (the username), flagging high-entropy strings (e.g., x8z9q2) that are characteristic of algorithmic bot generation. This defensive depth ensures that only high-quality, persistent user data enters your system.
email validation
fraud prevention
bot detection
marketing tools
list cleaning
Formulas
Shannon Entropy (Gibberish Detection)
To detect bot-generated usernames, we calculate the information entropy of the string. Higher entropy indicates more randomness, often a sign of automated generation.
H(X) = −n∑i=1 P(xi) log2 P(xi)
Where P(xi) is the probability of character xi appearing in the string.
Spam Score Algorithm
The final risk assessment combines multiple factors into a weighted sum:
Stotal = w1⋅IsDisposable + w2⋅MxMissing + w3⋅(H > 3.5)
Legend: H = Entropy Score, w = Weight Coefficient
Reference Data
| Category | Domain Examples | Risk Level | Typical Usage |
|---|---|---|---|
| Disposable / Burner | mailinator.com, trashmail.com, 10minutemail.com | CRITICAL | One-time verification bypass, spam bots. |
| Free Provider | gmail.com, yahoo.com, outlook.com | LOW | Standard personal users. |
| High Entropy User | [email protected] | HIGH | Bot-generated accounts on legitimate domains. |
| Corporate / Private | company.co, university.edu | SAFE | Business or academic entities. |
| Dead Domain | (No MX Records) | INVALID | Typo-squatting or defunct websites. |
| Role-Based | admin@, support@, sales@ | MEDIUM | Generic departmental aliases. |
Frequently Asked Questions
While we verify the existence of MX records, determining if a server is "Catch-All" (accepts all emails regardless of username) requires sending a real email, which is invasive. This tool performs passive DNS analysis to respect privacy protocols while ensuring the domain is capable of receiving mail.
Legitimate users usually select usernames with semantic meaning (e.g., "john.doe" or 'developer2024'). Bots generate random strings (e.g., 'x7z99qq') to bypass unique constraint checks. High entropy effectively flags these non-human actors even on reputable domains like Gmail.
Yes. The "Bulk Processor" mode runs entirely in your browser. However, for lists larger than 500 emails, we recommend processing in batches to avoid browser memory limits or rate-limiting from the DNS-over-HTTPS provider.
Our internal definition includes over 2,000 known burner providers. However, new disposable services appear daily. We combine the blocklist with MX checks and heuristic analysis to catch unknown disposable domains that might not yet be in the database.