Web Development Tools
Regex tester, cron expressions, HTTP status codes, IP address info, chmod, CIDR, diff checker.
This section collects the technical utilities that surface during server configuration, API design, and log analysis. Need to verify a regex against real input, see the next firing of a cron expression, check the canonical meaning of an HTTP status code, or compute CIDR ranges? These cover the "last-mile" engineering tasks.
Tools in this topic (8)
Regex Tester
Test regular expressions in real time with match highlighting and capture groups
Cron Expression Parser
Parse cron expressions into human-readable descriptions with next run times
HTTP Status Code Reference
Look up HTTP status codes with descriptions and categories
What Is My IP Address
Find your public IP address and view browser and device information
Chmod Calculator
Calculate Unix file permissions in numeric and symbolic notation
CIDR Calculator
Calculate IP ranges, subnet masks, and network info from CIDR notation
Diff Checker
Compare two texts and see differences line by line with highlighting
URL Parser
Break a URL into its components (protocol, host, path, query, fragment)
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