A single folder of code sits buried inside almost every website a person visits before lunch, quietly doing its job without a logo or a paycheck attached.
Nobody notices it. No one thanks it.
It just runs, silently, underneath banks, hospital systems, and shopping carts everywhere.
And now a team of researchers has put a number on exactly what that invisible layer is worth, and the number does not sit still.
So where did $8.8 trillion actually come from, and why does rebuilding it only cost pocket change by comparison?
How one small act of sharing multiplies into trillions
The reason the numbers diverge so wildly comes down to a single idea: free code gets written once, then reused by nearly every company that touches the internet, instead of being rebuilt from scratch inside each one. Harvard Business School researchers modeled this as a thought experiment, asking what would happen if every piece of free, shared code disappeared overnight and companies had to write replacements themselves.
Put plainly, one small act of sharing multiplies itself across millions of companies at once. A library gets written one time, then quietly reused by nearly every firm that touches the internet, which is why the demand-side number comes out roughly two thousand times higher than the build cost.
Picture the code itself, buried where nobody looks
To see this up close, consider a JavaScript library called core-js, an open source JavaScript library that boasts a strong popularity as a Polyfill that allows older browsers to use the latest JavaScript features . It is not flashy. Most users have never heard its name.
Yet it sits, as a transitive dependency, layered deep inside tools that bigger, more visible tools are built on. Its maintainer, Denis Pushkarev, known as zloirock on GitHub , has written the overwhelming majority of its code largely alone since starting the project over a decade ago.
The library is on hundreds of millions of websites and over 50% of the world’s most visited websites , from retail giants to household tech names. That kind of reach is exactly the pattern the Harvard researchers describe when they talk about demand-side value stacking up across firms that never wrote a line of it themselves.
And yet the person behind it has described income that fell from around $2,500 a month to roughly $400 , as one funding platform cut back its payout and another struggled to keep up, even as the project kept expanding into more products worldwide. Reach grew. Reward shrank. That contrast is the human shape of the trillion dollar gap.
Where the hardest numbers actually come from
The $8.8 trillion figure is not a guess pulled from a press release. It comes from a working paper out of Harvard Business School, built jointly with a researcher from the University of Toronto, published under the title The Value of Open Source Software.
The math starts with a simple thought experiment. The first number is the cost to rebuild the software once, using typical developer salaries and typical build times. The researchers estimate the supply-side value of widely-used OSS is $4.15 billion .
The second figure is what companies would actually spend if each had to recreate the same code separately, inside their own walls, instead of downloading it for free. The demand-side value is much larger at $8.8 trillion .
The team leaned on two large datasets to get there. One, Census II of Free and Open Source Software, tracks OSS embedded in commercial software products, and the other, BuiltWith, supplies data on OSS utilized in publicly facing websites, giving the researchers visibility into usage most companies never disclose on their own.
From that data, the researchers also found that firms would need to spend 3.5 times more on software than they currently do if OSS did not exist, with the top six programming languages in their sample comprising 84% of the demand-side value of OSS . JavaScript and Go rank among the heaviest contributors to that figure.
That scale explains why open source tooling keeps showing up in major company decisions. Tailwind Labs, the company behind the Tailwind CSS web-development framework, joined Shopify, an acquisition announced on September 9, 2026, by Tailwind founder Adam Wathan , covered in GCN’s report on Tailwind Labs, follows the same logic: buy into the thing everyone already depends on rather than build it from zero.
Where this estimate gets complicated, and where it breaks down
Even the researchers admit the number rests on assumptions that do not hold evenly everywhere. The demand-side total assumes every company would rebuild the exact same software from scratch, which ignores cheaper shortcuts some firms would likely find instead.
So the real figure for any single company could run lower in practice; indeed, the researchers themselves note the demand-side value ranges from $2.59 trillion to $13.18 trillion depending on which country’s programmer wages are used in the model. Still, the overall pattern, enormous value from small effort, holds across the industry. Critics on technical forums have pointed out that dividing the trillions evenly across top contributors produces per-person numbers that look implausible on their face.
Even so, the concentration finding holds up across multiple versions of the research. 96% of the demand-side value is created by only 5% of OSS developers .
That concentration is where supply chains get fragile. When a handful of people hold up software worth trillions to others, a single burnout or pay dispute can ripple into products built by companies that have never heard the maintainer’s name, a risk security teams have flagged for years without a clean fix.
What the gap means for the code running your phone right now
None of this is abstract. The same layered dependency pattern that props up core-js sits underneath the apps on every phone, the dashboards companies trust, and the checkout pages people click through without a second thought.
So far, a handful of companies have started funding maintainers directly or sponsoring foundations that support critical projects. But those efforts remain small and uneven, far short of matching the trillions in value the software quietly generates every year.
Even without a tidy fix, the research itself marks a shift. Putting a real number on free code turns an invisible favor into a line item worth arguing about, which is often the first step toward someone finally agreeing to pay for it.
