IPv4 to Binary Converter

How it is calculated

An IPv4 address is four numbers (octets) separated by dots. In address-to-binary mode each octet, 0 to 255, is written in base 2 and padded with leading zeros to exactly eight digits, then the four groups are joined with dots. In binary-to-address mode each group of up to eight 0s and 1s is read as a base-2 number, b7·128 + b6·64 + b5·32 + b4·16 + b3·8 + b2·4 + b1·2 + b0, and printed in decimal.

In both directions the tool also reports the 32-bit integer value a·2²⁴ + b·2¹⁶ + c·2⁸ + d. The input must have exactly four dot-separated parts. Decimal octets must be digits only and not above 255; binary groups may only contain 0 and 1, and a group shorter than eight digits is accepted and read as a number (so 1010 means 10). Anything else returns no result. Only IPv4 is covered, not IPv6.

Common mistakes

• Leaving the direction set to address-to-binary while entering binary digits, or the reverse. A binary string in the wrong mode is rejected, as is a decimal address in binary-to-address mode.
• Writing an octet above 255 (such as 192.168.1.256) or giving only three parts. Both return nothing rather than a corrected address.
• Leaving out the padding zeros when typing binary by hand. A short group such as 1 or 1010 is accepted and read as 1 or 10, so 11000000.10101000.1.1010 gives 192.168.1.10 and can hide a typo. Write all eight digits per group.
• Entering a binary group with digits other than 0 or 1, for example 11000002. Only 0 and 1 are allowed in that mode.
• Entering a CIDR prefix such as 192.168.1.10/24. The slash part is not accepted; enter the address alone.