Quantifying opportunity cost with a deliberately "simple" web app
Hi HN, A while ago I had a mildly depressing realization. Back in 2010, I had around $60k. Like a "responsible" person, I used it as a down payment on an apartment. Recently, out of curiosity, I calculated what would have happened if I had instead put that money into NVIDIA stock. I should probably add some context. For over 10 years I've worked as a developer on trading platforms and financial infrastructure. I made a rule for myself - never trade on the market. In 2015, when Bitcoin traded about 300 usd, my brother and I were talking about whether it was a bubble. He made a bold claim that…
Quantifying opportunity cost with a deliberately "simple" web app launched on February 24, 2026 with 28 votes, #676 of 16,627 launches that month and more than 95% of that year's launches.
In plain words
Quantifying Opportunity Cost is a web application that calculates what would have happened if past financial decisions had been made differently. Users input a historical amount of money and an alternative investment they didn't make, and the tool shows the hypothetical outcome. Built by a developer with over a decade of experience in trading platforms and financial infrastructure, it provides a simple interface for exploring the "what if" scenarios around major investment decisions. The app addresses the tension between financial knowledge and personal investment choices.
written from the facts on this page · September 2026
From the sources
Calculate how much money you missed out on by not buying Bitcoin, Nvidia, and other assets.
STATUS: BULLET DODGED. CAPITAL SAVED:' : '> STATUS: MISSED WEALTH. ESTIMATED LOSS:'"> We are not here to teach you how to invest. We are here to make you feel every cent that slipped through your fingers. You could have been free. You could have owned that island. You could have bought the future, but you chose to click 'SELL' . Every calculation here is a monument to a wrong decision. Every number is a ghost of the wealth youfrom shouldhavebought.com
In the maker’s words, at launch
Hi HN, A while ago I had a mildly depressing realization. Back in 2010, I had around $60k. Like a "responsible" person, I used it as a down payment on an apartment. Recently, out of curiosity, I calculated what would have happened if I had instead put that money into NVIDIA stock. I should probably add some context.…
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