Developer Utilities

HTTP, security, network, and request utilities for developers

Cron Expression Parser

Parse and explain cron expressions

HTTP Headers Parser

Convert raw HTTP headers to JSON and back

HTTP Status Codes

Search and reference common HTTP status codes

User-Agent Parser

Detect browser, OS, and device from user-agent strings

IPv4 CIDR Calculator

Calculate IPv4 subnet ranges, masks, and usable hosts

Chmod Calculator

Convert Unix permissions between octal and symbolic modes

Cache-Control Parser & Builder

Parse, normalize, and check HTTP caching directives

CSP Header Builder & Analyzer

Build and inspect Content Security Policy headers

cURL Builder & Fetch Converter

Build cURL requests or convert supported cURL input to fetch

QR Code Generator

Generate QR codes from text or URLs

Markdown Preview

Preview and convert Markdown to HTML

About Developer Utilities

Our developer utilities are designed to help developers work more efficiently. All tools are free to use, require no registration, and process data client-side for maximum privacy.