PhishCheck - Phishing & Spam Email Checker od Md. Habibur Rahman

PhishCheck is a private, offline phishing and spam email checker for Firefox. Open a message in your webmail, and PhishCheck analyses it locally to show whether it looks like phishing or spam, with clear explanations and supporting evidence.

🔒 Your privacy comes first. All analysis happens on your device. No servers, AI services, analytics, or tracking. Your email never leaves your computer.


🛡 Clear, Evidence-Based Results

Every message receives a clear status:

🟢 Likely Safe
🔵 Low Risk
🟠 Suspicious
🔴 High Risk

Each status includes both an icon and a text label, so colour is never the only indicator.

⚡ Automatic Scanning

Scan messages automatically when you open them. The toolbar badge displays OK, LOW, WARN, or HIGH. You can independently disable automatic scanning and the toolbar badge.

🔍 Explanations for Every Warning

See what PhishCheck detected, why it matters, and what you can do about it. No unexplained scores.



Detect potential sender impersonation and suspicious address patterns, including:

🔸 Display names that do not match the actual email address
🔸 Look-alike and typo-based domains
🔸 Unicode and punycode domain tricks
🔸 Brand impersonation
🔸 Mismatches between the sender and Reply-To addresses


Examine links without visiting them. PhishCheck checks for:

🔸 Differences between visible link text and the actual destination
🔸 IP-based and obfuscated addresses
🔸 Link shorteners
🔸 Unencrypted HTTP links
🔸 Login pages hosted on unrelated domains
🔸 Redirect wrappers

🚫 PhishCheck never visits a link.


Identify common phishing and spam indicators, including:

🔸 Requests for passwords or verification codes
🔸 Payment and gift-card scams
🔸 Threats and false urgency
🔸 Executive and CEO fraud pressure tactics
🔸 Prize scams and advance-fee scams
🔸 QR-code lures
🔸 Classic spam wording

🧠 Context-aware detection: PhishCheck considers context to help avoid unnecessary warnings. Ordinary messages about verifying an email address or invoices are not flagged simply because they contain those terms.


Inspect attachment file names only to identify suspicious patterns, including:

🔸 Executables and scripts
🔸 Double extensions, such as invoice.pdf.exe
🔸 Macro-enabled documents
🔸 HTML files
🔸 Archives

🔒 Attachments are never opened or downloaded.


PhishCheck is designed to keep your email private and your decisions in your hands.

🔒 Offline analysis: No network requests of any kind.

⚙ Sensitivity settings: Choose Conservative, Balanced (default), or Strict.

✅ Trusted domains: Maintain a list of domains you trust.

📊 Local scan counts: View scan counts stored on your device.

📋 Copyable security report: Copy a report without including message text.

🎛 Optional controls: Disable automatic scanning and the toolbar badge.


PhishCheck supports:

📧 Gmail
📧 Outlook (outlook.live.com, office.com, office365.com, and cloud.microsoft)
📧 Yahoo Mail
📧 Proton Mail

🌐 You can also try a generic webmail parser on other webmail pages by pressing the relevant button.


PhishCheck helps you assess suspicious messages, but it cannot guarantee that an email is safe or malicious. It cannot read SPF, DKIM, or DMARC information from a webmail page.

🛑 PhishCheck never deletes, moves, reports, blocks, replies to, or forwards messages.

👤 You always make the final decision.


PhishCheck requests only the permissions needed for its functionality.

💾 storage
Save settings, trusted domains, and scan counts locally.

🌐 Host access
Read the open message through a content script so it can be analysed locally on supported webmail sites.

🖱 activeTab + scripting
Place the reader into a supported webmail tab that was already open before installation or update, and support the optional generic webmail parser on another page only after you click its button.

🔒 No unnecessary access: PhishCheck does not request access to tabs, cookies, web requests, downloads, browsing history, or all websites.


✅ No data collection: PhishCheck collects no user data. Its data collection permission is set to ["none"].

📴 No network requests: No network requests of any kind are made, as enforced by tests/privacy.test.js and tests/offline.test.js.

💻 Local storage only: The extension stores the following locally:

🔸 Settings
🔸 Trusted domains
🔸 Per-day scan counts
🔸 An in-memory, per-tab marker of the last counted message

🔐 Your email content is analysed on your device and never leaves your computer.


📂 Category: Privacy & Security

🔖 Tags: phishing, spam, email, security, privacy


📧 Support email: habiburhridoy01@gmail.com

📄 Privacy policy: Paste the contents of PRIVACY.md into the Privacy Policy field on the Firefox Add-ons submission form. The same text is available on the options page.

⚖ License: Select All Rights Reserved on the AMO submission form to match the repository's LICENSE file.

🔍 PhishCheck helps you recognise suspicious email patterns, understand the evidence, and make more informed security decisions, all while keeping your email on your own device.