Technology & Internet Calculators

Base64 Encoding Explained: What It Does and What It Doesn't

Base64 converts arbitrary binary data into a text-safe string using a 64-character alphabet — it's a format conversion for safe transport through text-only channels, not encryption or compression, and it makes data larger, not smaller, by roughly a third.

CIDR Notation Explained: What /24, /26, and Other Prefixes Mean

The number after the slash in CIDR notation (like the 24 in 192.168.1.0/24) is a bit count, not a percentage or a version number — it tells you how many of the address's 32 bits are fixed as the network portion, and every single bit of difference doubles or halves the number of addresses in the block.

How IPv4 Subnetting Is Calculated

An IPv4 subnet's network address, broadcast address, and usable host range all come from applying the CIDR prefix as a bitmask to the IP address — with a special two-address exception for point-to-point /31 links.

How IPv6 Subnetting Is Calculated

IPv6 subnetting works the same way as IPv4 — masking the address by a prefix length — but with 128-bit addresses instead of 32-bit ones, producing address counts so large they're shown as exact text rather than a rounded number.

How Password Entropy Is Calculated (And Why Length Beats Complexity)

Password entropy — a measure of how hard a password is to guess by brute force — is calculated as length multiplied by the base-2 logarithm of the character pool size, and a longer password from a smaller character set can have MORE entropy than a shorter, more "complex-looking" password with symbols mixed in.

How to Calculate a Subnet Mask, Network Address, and Usable Host Range

Given an IPv4 address and a CIDR prefix (like /26), the subnet mask, network address, broadcast address, and usable host range are all derived through bitwise AND/OR/NOT operations on the address and mask — not separate lookups, but four related outputs of the same underlying arithmetic.