Validators & Extractors
Free online validators and extractors — validate email, credit card, IBAN, ISBN, UUID and SQL, and extract emails, URLs and phone numbers from text. All checks run in your browser.
10 free validators & extractors — all browser-based
Email Validator
Validates an email address against RFC 5322 syntax rules and common practical constraints (no consecutive dots, valid TLD length, quoted local parts), reporting whether the address is valid and why.
Credit Card Validator
Checks whether a card number passes the Luhn checksum used by real issuers and detects its network (Visa, Mastercard, Amex, etc.).
IBAN Validator
Validates an International Bank Account Number using the ISO 7064 mod-97 checksum and identifies its country and check digits..
ISBN Validator
Validates an ISBN-10 or ISBN-13 using its checksum (mod-11 for ISBN-10 with an optional X check digit, mod-10 with alternating 1/3 weights for ISBN-13), auto-detects the format from the cleaned digits, and converts between ISBN-10 and ISBN-13 via the 978 prefix.
UUID Validator
Validates a UUID's format and identifies its RFC 4122 version (v1-v8) and variant, flagging the special nil and max UUIDs..
URL Validator
Validates a URL against the URI generic syntax (RFC 3986), checking the scheme, authority, path, query, and fragment, with optional enforcement of allowed schemes, default-port matching, and punycode host detection.
SQL Validator
Validates SQL syntax with a lightweight tokenizer covering SELECT, INSERT, UPDATE, DELETE, CREATE, and common clauses, reporting unclosed strings, parentheses, and unterminated statements.
Email Extractor
Extracts every email address from pasted text using a practical RFC 5322-style pattern, with optional deobfuscation of “at”/“dot” notation, deduplication, and case-insensitive matching.
URL Extractor
Extracts every http(s), ftp, and bare www link from pasted text using a practical regex, strips trailing punctuation, optionally normalizes bare www links to https, and deduplicates results.
Phone Number Extractor
Extracts international and North-American phone numbers from pasted text using a tolerant regex that handles +, parentheses, spaces, dashes, and dots, with optional deduplication and output normalization to raw, E.164, or digits-only form.
Validating identifiers
The Email Validator checks RFC 5322 syntax plus common typos, and the Credit Card Validator runs Luhn plus BIN lookup.
IBAN and ISBN validators verify check digits per their respective standards.
Extracting data from text
Paste a document into the Email or URL Extractor to pull every matching string into a deduplicated list.
Frequently asked questions
Does the credit card validator store card numbers?
No. Validation runs entirely in your browser; no card data is ever transmitted or stored.