Data Validators
7 tools to format, validate, and process data in your browser.
JSON Schema Validator
Validate JSON payloads against JSON Schema drafts using Ajv with configurable strictness, coercion, and error reporting — all offline in your browser.
Email Address Validator
Stop sending emails to invalid addresses! Validate email syntax instantly with comprehensive checking for format errors, domain verification, and deliverability insights. Supports international domains and disposable email detection. Free, works offline, unlimited validations.
Phone Number Validator
Stop manually checking phone number formats! Validate phone numbers from 200+ countries with automatic country detection, E.164 format verification, and carrier analysis. Perfect for form validation, CRM data cleanup, and contact verification. Free, works offline, unlimited validations.
Credit Card Validator
Stop processing invalid credit cards! Validate card numbers instantly with Luhn algorithm verification, automatic brand detection (Visa, Mastercard, AmEx, Discover), expiry date checking, and BIN information lookup. Perfect for payment form validation and e-commerce testing. Free, works offline, completely secure.
IBAN Validator
Stop sending payments to invalid bank accounts! Validate International Bank Account Numbers (IBAN) instantly with mod-97 checksum verification, country code validation, and bank information lookup. Supports 70+ countries including all SEPA regions. Free, works offline, complete privacy.
URL Validator
Stop sharing broken or dangerous links! Validate URLs instantly with comprehensive security analysis, domain verification, scheme checking, and SEO recommendations. Detects phishing attempts, malformed URLs, and accessibility issues. Perfect for web development, content management, and link safety. Free, works offline, unlimited validations.
HTML5 Validator
Validate HTML5 markup for unclosed tags, structural issues, and malformed attributes with optional prettified output and Markdown reports.
JSON Schema Validator
Validate JSON payloads against JSON Schema drafts using Ajv with configurable strictness, coercion, and error reporting — all offline in your browser.
Email Address Validator
Stop sending emails to invalid addresses! Validate email syntax instantly with comprehensive checking for format errors, domain verification, and deliverability insights. Supports international domains and disposable email detection. Free, works offline, unlimited validations.
Phone Number Validator
Stop manually checking phone number formats! Validate phone numbers from 200+ countries with automatic country detection, E.164 format verification, and carrier analysis. Perfect for form validation, CRM data cleanup, and contact verification. Free, works offline, unlimited validations.
Credit Card Validator
Stop processing invalid credit cards! Validate card numbers instantly with Luhn algorithm verification, automatic brand detection (Visa, Mastercard, AmEx, Discover), expiry date checking, and BIN information lookup. Perfect for payment form validation and e-commerce testing. Free, works offline, completely secure.
IBAN Validator
Stop sending payments to invalid bank accounts! Validate International Bank Account Numbers (IBAN) instantly with mod-97 checksum verification, country code validation, and bank information lookup. Supports 70+ countries including all SEPA regions. Free, works offline, complete privacy.
URL Validator
Stop sharing broken or dangerous links! Validate URLs instantly with comprehensive security analysis, domain verification, scheme checking, and SEO recommendations. Detects phishing attempts, malformed URLs, and accessibility issues. Perfect for web development, content management, and link safety. Free, works offline, unlimited validations.
HTML5 Validator
Validate HTML5 markup for unclosed tags, structural issues, and malformed attributes with optional prettified output and Markdown reports.
Related categories
› About data validators
Validate data formats, contacts, and input fields Every tool runs client-side, so you can work with internal or sensitive content without upload workflows.
Common workflows include validation, quick conversion, and cleanup for API payloads, docs, spreadsheets, and operational data.