IPBitTools, for when 64 bits stops being enough

Field notes

The toolkit works across several representations—hexadecimal, decimal, binary, and octal—and exposes both signed and unsigned interpretations of a fixed-width value. Its network-oriented tools return IPv6 validation details, canonical or bracketed formatting, CIDR ranges, and subnet addresses; the UUID converter supports numeric comparison, sorting, and diffing. The page emphasizes exact BigInt arithmetic to avoid the precision loss associated with ordinary JavaScript numbers.