Regex TesterLive matches and groups
Cron ParserNext runs in plain English
Epoch / TimestampConvert Unix time both ways
Number BaseBinary, octal, decimal, hex
Chmod CalculatorUnix permissions, octal and symbolic
CIDR / Subnet CalculatorRanges, masks and host counts
Time Zone ConverterOne time across time zones
User-Agent ParserBrowser, OS and device from a UA string
UUID v4Random UUIDs, one or many