validator

Free online XML validator — check well-formedness, view parsed structure tree, find errors with line numbers. Pretty-print messy XML. No uploads, client-side only.

Validate Base64 strings, detect standard vs URL-safe variants, see decoded preview. Measure data size and check padding. Free browser-based tool, no uploads.

Validate IPv4 and IPv6 addresses. See IP type, class (private/public/loopback), binary representation. Bulk mode validates multiple IPs. Free, client-side.

JSON Validator — Paste JSON and instantly see if it is valid or invalid. Get formatted tree view, size, depth, and key count stats. All validation happens client-side.

URL Validator — Validate and break down any URL into protocol, hostname, port, path, query parameters, hash, username, password, host, and origin. Bulk mode supported.

UUID Validator — Validate any UUID, detect the version (v1, v4, v7, etc.) and variant, see alternative formats (canonical, uppercase, no-dashes, URN). Bulk mode for multiple UUIDs.

Validate IBANs using the official mod-97 checksum. Supports 80+ countries. Free, instant, and runs entirely in your browser.