Developer Tools

Calculate network address, broadcast address, usable host range, and host count from an IPv4 CIDR block.

Build common cron expressions for scheduled jobs and copy a readable explanation.

Generate responsive CSS clamp values for fluid typography and spacing between viewport widths.

Generate a quick DNS record reference for A, AAAA, CNAME, MX, TXT, SPF, DKIM, DMARC, CAA, and NS records.

Infer a starter JSON Schema from a sample JSON object or API response.

Generate a Markdown table of contents from heading text and document outlines.

Format SQL queries for easier reading, debugging, code review, and documentation.

Write Markdown and preview rendered HTML in a responsive side-by-side workspace.

Calculate selector specificity scores to debug CSS overrides and cascade behavior.

Generate cURL commands for quick API debugging, docs examples, and terminal testing.

Inspect pasted email headers for received hops, authentication results, sender fields, and routing clues.

Parse pasted HTTP request or response headers into a clean key-value table for debugging web responses.