Meet the Founder of Omni Calculator

Some startups begin with a polished business plan. But Omni Calculator started because a guy just wanted to learn JavaScript.

Way back in 2011, when most online calculators still looked like forgotten relics from the early web, Mateusz Mucha from Kraków, Poland, decided to create something smarter. Instead of the usual setup, filling in boxes one after another and then hitting a big “Calculate” button, he built a Percentage Calculator that could work in any direction, instantly. Now you could type in pretty much any field, in any order, and it would give you the answer right away. It was a game-changer on the usual calculator thing.

What began as a little side project quickly evolved into a mobile app and surprisingly hit 5 million downloads and was translated into 15 languages.

Then, in 2014, after joining a Berlin startup accelerator, Omni Calculator, as we know it today, was born. It wasn’t huge at first, with just about 20,000 visits a month by 2016.

Fast forward to 2026, and it generates up to 20 million visits every month, with 3800+ calculators covering everything from science and finance to health and everyday life. Along the way, it caught the attention of big names like Google, The Guardian, The New York Times, and National Geographic. Mateusz himself has been recognized multiple times by BRIEF as one of Poland’s Top 50 Most Creative People in Business.

 
One of those big “aha” moments for Omni came from something surprisingly simple: Mateusz realizing that people kept sticking with calculators designed for their exact situation.

That idea still drives Mateusz today. It was never just about making calculators, but more about removing friction from everyday decisions. Whether you’re trying to figure out mortgage payments, how much pizza to get, or even wrestling with a tricky physics problem before an exam, Omni has you covered.

From Sales Tax and APY calculators to a more personalized Calorie Deficit Calculator, Omni’s calculators are pretty handy for solving all sorts of everyday questions. And the best moments usually come straight from the users, like someone with diabetes who told Mateusz that the Warsaw Method Calculator was an actual “lifesaver“, helping them calculate insulin doses several times a day.

Besides the usual handy tools, Omni got a reputation for making calculators that feel oddly specific, fun, or just quirky enough to make you stop and click. Like, ever wondered how long you should really chill a drink in the freezer? Or how much cash you’d actually save by quitting social media? Or what might happen if you fell into a black hole?

 
As Omni grew, Mateusz assembled an international team of scientists, engineers, academics, creatives, and specialists from wildly diverse backgrounds. What really ties them together is a shared hunger for curiosity and problem-solving, and a real passion for making knowledge easier to grab onto.

Mateusz believes one of the biggest things that helped shape Omni’s culture was figuring out how to actually give talented people real autonomy instead of trying to control every little thing himself. Also, running a company isn’t nearly as glamorous as people might think, but it’s mostly about thinking, analyzing, and meetings.

Even if AI is shaking up the internet, Omni isn’t forgetting what got it here: solid logic, expert-reviewed calculations, and breaking down tricky stuff into simple terms. Instead of digging through endless calculators, Omni aims for a future where you can just explain your problem and instantly get a tool made just for it.

So, what advice would Mateusz give to other founders?