Key Difference: 32 bit and 64 bit are generally associated with the processors of the computers. A 32 bit computer can only access a limited amount of memory. On the other hand, a 64 bit computer can use nearly unlimited amount of memory.

Bit stands for binary digit. It is the smallest unit of information in computing. A byte consists of 8 bits. Many people are not aware with the differences between 32 and 64 bit computers. However, this term is generally associated with the memory component of the computer. The bit attribute in this context is related to the width of the registers in which the CPU keeps the data. This data is kept in the registers so that it can be accessed quickly.

A CPU with a 32 bit processor means that it has a small space in the CPU’s register system than in comparison to the 64 bit registers. A 32 bit computer is able to access only 3.25 GB of RAM. In case, the user wants to expand the RAM, he might add external RAM. However, these RAM would not be utilized by the computer. A 64 bit processor can address more memory in comparison to the 32 bit computer. It has the capability to use and handle unlimited RAM. However, there is some theoretical limit but that goes to approximately 17 billion gigabytes of RAM. 64 bit architectures have been developed in order to meet the continuous growing demands of servers.

Comparison between 32 bit and 64 bit:

Compatibility of 32 bit CPU:

Compatibility of 64 bit CPU:

(Compatibility tables have been taken from techsupportalert.com)

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