This Is the Total Storage Capacity of the Human Brain

As humans, we like to think of ourselves as special and mysterious beings. Curious organisms with emotions, thoughts and everything that makes up what we think of as the soul. Which is why describing the human brain as a meat-based computer is sure to inspire frowns. While I’m not trying to minimize the wonder packed inside our brainpan, what happens in there isn’t pure magic.

Our brains use electrical current to operate, and do everything from jerk around our limbs to storing and recalling memories. Here, again, science arrives to curb-stomp the poetry of being, by explaining how memories are stored, instead of a swirling aether cloud of past experiences. They’re created when synapses in your brain establish connections, and if it’s a memory you try to hold onto, that connection is strengthened over time.

It might not be as whimsical as endless halls of paintings and notes tucked away in a mind palace, but it’s still cool in its own way, your brain chiseling things it needs to remember into itself like marble. It also means that, like a marble slab, even the most massive will eventually run out of space.

The other most common reference to memory these days is in the realm of computers, and in an unsettling twist, it turns out that your brain’s storage and your hard drive’s storage can both be measured with the same unit: the bit. With a limited number of synapses, each able to store a limited amount of information, science has been able to estimate the total storage capacity of the human brain. 

For a long time, it came in at around 100 terabytes, which is impressive, but one that puts us within spitting distance of modern computer storage. The estimate came from estimating the number of synapses in the brain, and assuming that each could communicate one bit of information.

If you feel underwhelmed, there’s good news: Scientists have only recently discovered that synapses seem to be able to hold much more than a single bit of information, somewhere between four and five bits. That would put our capacity for memory into the staggering realm of petabytes. A petabyte is just over a million gigabytes — 1,048,576 GB to be exact.

Scientist-suggested figures start at a petabyte, with some throwing out the figure of 2.5 petabytes, an absolutely bonkers amount of information. Which is a relief, in my eyes. It’s good to know that we’ve still got a leg up on computers. It’s also reassuring that, at least for now, nobody would be able to download anybody to their laptop.