About IsThisValid.com

IsThisValid.com is a free verification hub. Whether you've received a suspicious text, want to check a sketchy link before clicking it, or need to validate an email address, we have a tool for it — no account, no sign-up, no data stored.

All three tools run directly in your browser and return results in seconds.

1. Email Validator — checks whether an email address passes RFC 5322 syntax rules, belongs to a known disposable-email provider (3,500+ domains), has valid DNS MX records, and (optionally) whether the mailbox actually exists. Results are scored 0–100. Try it →
2. URL Safety Checker — checks URLs for phishing signals, suspicious keywords, brand-squatting, punycode tricks, IP addresses masquerading as domains, URL shorteners, and known malware/phishing lists via the Google Safe Browsing API. Try it →
3. Text / SMS Scam Detector — paste any suspicious message and our AI (powered by Anthropic Claude) analyses it for scam, smishing, spam, and social-engineering patterns. It flags specific phrases and explains its reasoning. Try it →

Scams are getting harder to spot. Smishing texts impersonate banks and couriers convincingly. Phishing URLs differ from the real thing by a single character. Disposable email addresses pollute sign-up flows. None of these problems require expensive software to catch — they just need a quick, reliable check.

IsThisValid.com is deliberately simple. No logins, no dashboards, no plans to upsell you into a SaaS tier. Just paste, check, done.

Email Validator — validation runs in two layers: local checks (syntax, TLD, disposable domain list, MX DNS) happen in milliseconds with no third-party calls. If the optional Emailable integration is active, we also perform an SMTP-level handshake to verify mailbox reachability.

URL Safety Checker — nine local heuristics run first (no network calls, instant). If the URL passes, we make a HEAD request to check reachability, then query the Google Safe Browsing API against its threat database.

Text / SMS Scam Detector — your message is sent to our server and forwarded to Anthropic's Claude API with a strict system prompt that instructs the model to classify the message and extract specific red flags. The output is validated against a schema before being returned to you. Results are cached for 24 hours (by a one-way hash of the message) to avoid redundant AI calls for the same viral scam text.

None of the content you submit — email addresses, URLs, or text messages — is permanently stored on our servers. Text messages submitted to the scam detector are forwarded to Anthropic for analysis; a one-way cryptographic hash may be cached briefly to avoid duplicate calls. For full details, see our Privacy Policy.

IsThisValid.com is free to use. To keep the lights on, we display advertisements via Google AdSense. Advertising never affects our results — we have no commercial relationship with any service we check against, and no financial incentive to report a result as safe or unsafe.

Questions, feedback, or bug reports? Reach us at hello@isthisvalid.com.