A URL validator checks whether a URL is structurally valid and safely parseable before you store it or use it in redirects, webhooks, or API calls. It helps catch missing schemes, invalid hostnames, illegal characters, and encoding issues. SWEDevTools: Prism validates locally in your browser so you can test real callback URLs and signed query strings without uploading them to third-party sites.
Usually no. URL grammar is complex. Prefer a real parser, then enforce business constraints (allowed schemes/hosts/ports).
No. Structural validation does not check DNS or network reachability.
Without a scheme, many parsers treat the value as relative. For redirects and webhooks, require explicit schemes.
Not literally. Spaces must be percent-encoded (%20), or represented as + in certain form-encoded query contexts.
They follow different rules. + often means space in query decoding, but in paths it is typically a literal plus.
Technically yes (https://user:pass@host), but it is discouraged and often blocked by security tooling.
Parse the URL, then enforce a strict allowlist of origins/paths. Never redirect to arbitrary user-provided domains.
IDNs may be normalized to punycode internally. Normalize consistently before comparing if you rely on exact string matching.
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