The reason why WhatsApp groups support 256 participants maximum

Despite being the most used messaging application on Earth, WhatsApp still keeps the odd secret that not everyone knows. For example, did you know that it wasn’t even a messaging app at first? Or that the maximum number of participants in a group has a technical explanation?

We have already talked to you about the first case, but until now, we have not explained why WhatsApp groups admit “only” 256 people. Neither 255 nor 257. And the truth is that, while rivals like Telegram continue to increase this number to unsuspected limits – today there are already 200,000 people who can be part of a Telegram group, and going up – WhatsApp remains faithful to this curious and technical figure released in 2016.

WhatsApp groups only support 256 people, but there is a reason.

WhatsApp groups only support 256 people but there is a reason

To understand why WhatsApp, at the time, decided to choose this particular figure as the maximum number of members that can be added to a group, it is necessary to take into account some of the fundamentals of computing, such as the binary system it uses two digits to be represented –0 and 1–.

As the user dat_sylveon points out on RedditWhatsApp stores each user in a group with a unique identifier. Therefore, taking into account that 256 is the maximum number of participants and that the binary system uses two digits, we can deduce that each unique user identifier uses 8 bits since two raised to 8 is equal to 256, which is the maximum number of unique identifiers that can be obtained.

The truth is that 256 is one of the most critical numbers in the field of computer science since it is the most significant number of elements that can be represented with a single byte –eight bits, or what is a binary system would be “eight some”-. For example, 256 is the maximum number of colors found in a GIF or characters in the ASCII language.

WhatsApp could easily assign unique identifiers made up of a more significant number of bits. It is possible that, over time, 2 bytes will be allocated instead of 1 as before, which would result in a maximum number of participants of more than 65,000 people per group, a figure that, today, would be unnecessary to the vast majority of platform users.

We do not know if WhatsApp will increase this limit sooner or later and, if it does, to what maximum number of participants. But at least we already know why, after extending the limit for the first time in the groups, 256 was the number chosen by the company.