/ PAC FILE // validator
Test and validate your Proxy Auto-Configuration (PAC) files instantly. Zero-trust and Privacy-first: the JavaScript evaluation is performed 100% locally in your browser. Your PAC logic is never sent to our servers.
PAC Script
Routing Tester
Security Sandbox: Execution runs entirely in your local browser sandbox. It does not perform actual DNS resolution (`dnsResolve`, `isInNet`) and instead relies on safe stubs for evaluation.
About PAC File Validation
A Proxy Auto-Configuration (PAC) file is a JavaScript function that determines whether web browser requests should go directly to the destination or be forwarded to a web proxy server.
Testing PAC files is traditionally difficult and prone to errors because syntax mistakes can cause silent network failures across an entire organization. This tool provides a secure sandbox to evaluate the FindProxyForURL(url, host) logic against specific URLs before deploying to production.
Included PAC Functions Support:
Our local evaluation engine automatically injects polyfills for common PAC functions so your code works out of the box:
- isPlainHostName(host)
- dnsDomainIs(host, domain)
- shExpMatch(url, pattern)
- localHostOrDomainIs(host, hostdom)
- dnsDomainLevels(host)