For years, Calculum founder Oliver Belin was selling a fix to a problem most companies didn’t realize they had. A problem that is as invisible as it is large.
Most businesses obsess over pricing, revenue, and cost savings. Very few take a hard look at how they pay suppliers, and what that actually costs them. Calculum was built around that gap, sitting between finance and procurement to help companies optimize payment terms and free up working capital.
“We have created something new. We don’t have real competitors,” Belin [pictured above] told Refresh Miami. Early on, that made growth harder, not easier. “You have to create the market. You have to educate the market. Nobody has the idea to search for you.”
For the first couple of years, adoption was slow. Then something shifted.
“Suddenly, we see a strong growth, 3x year on year,” he said. The exact reason is hard to pin down, but one thing is clear: customers are sticking. “We have happy clients. They’re renewing.”
Those clients skew large. Companies like Philips and Campbell’s now use the platform, even though Calculum originally set out to serve the mid-market.
“We ended up with the largest companies in the world,” Belin said. Expanding to companies in the $200 million to $1 billion range is now back on the roadmap.
The insight behind the product is simple. If a company pays suppliers earlier than the market standard, it’s effectively providing financing.
“You’re financing them,” Belin said. “This has a cost.”
In some cases, companies are enabling suppliers to offer better terms to their competitors. Calculum analyzes supplier data, identifies where terms are misaligned, and highlights where changes are most likely to succeed.
“You can never pick up the phone and call 20,000 suppliers,” he said. “So the platform tells you where to focus.”
The product is now expanding beyond payables. A new offering will help companies manage receivables, meaning how they negotiate terms with their own customers. The goal is to cover both sides of the transaction.
AI is part of that evolution, though Belin is careful about how it’s used.
“Our clients are very conscious. Like, ‘where does my data go and how you use it?’” he said. Instead of relying on public data, Calculum builds models using internal company information, with AI mainly supporting data enrichment and real-time updates.
Looking ahead, the bigger shift may come from automation.
“This year, I think the market is ready to get started with AI autonomous negotiations,” Belin said. Today, some companies already outsource supplier negotiations to Calculum. The next step is letting AI handle those conversations, at least for smaller, non-critical vendors.
Miami has played a protagonistic role in Calculum’s growth thus far.
“Our IT development team is all Spanish speaking,” he said, pointing to the alignment with talent across Latin America. Miami’s role as a financial hub, especially in trade finance, has helped the company stay close to its customers, according to Belin.
Calculum’s footprint in Miami is still relatively lean, with 15 employees locally and around 35 overall, but its setup says a lot about the kind of city Miami has become.
The company shares office space with Music Week organizers and sits next door to Space, the iconic electronic music club. On any given morning, you might find engineers logging in for the day while the remnants of a 24-hour party spill out onto the street.
For Belin, it’s a fitting contrast. A fintech company working on complex supply chain finance problems, operating just steps away from one of the most recognizable names in global electronic music.
It’s a small but telling snapshot of Miami right now. Finance, tech, and culture, all layered on top of each other, sometimes quite literally under the same roof.
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