Turning Excel Into Business Software

Yes, you can turn an Excel spreadsheet into a business app.

In fact, many of you already have—you just don’t call it that.

Spend five minutes scrolling through any Excel power-user forum and you’ll see the same quiet confessions: spreadsheets running ticketing systems, billing processes, even entire operations.

Like this one post we came across on Reddit:

“I’ve built workbooks that let me track employee tickets, inventory, time keeping, and customer billing. The only problem is I’m the only one who really knows how to fix it if anything goes down. I would like to give this a UI and essentially make it idiot proof so that I can drop employees in to positions that would need the software with minimal training.”  

Two pain points jump out:

• One person ends up as the sole keeper of critical knowledge.
• Without a front end, the spreadsheet is too fragile for anyone else to use.

That tension between Excel’s hidden power and its lack of accessibility shows up everywhere. Especially in insurance, where entire pricing engines and underwriting processes often live in files that only a handful of people can operate.

Every Spreadsheet is Already a Business App

Look closer at your files.

What you think of as a “just a spreadsheet” is often a disguised business application.

• That time-tracking sheet? It’s a workforce management tool.
• The ticket log? A lightweight customer support pipeline.
• A sales tracker? A CRM in cells.
• Your product inventory workbook? It’s running procurement.
• An invoicing file? A billing system, fragile but functional.

The only difference between these files and “real” software is that Excel hides its logic behind rows and columns.

And in insurance, it goes even further:

• An Excel rating model is a pricing engine.
• A sheet full of underwriting rules is an underwriting workbench.
• A reserve calculator is a claims reserve app.
• A broker spreadsheet is a commissions system.

These aren’t throwaway tools. They represent years of refinement, testing, and real-world decision-making. They carry regulatory trust and competitive advantage. They are the IP that makes your business unique.

And that’s exactly why companies hesitate to replace them. The models already work. They’ve been proven under pressure. They’re central to how you serve customers.

But as long as the data stays locked inside cells, only a few people can use it—and the business can’t scale or deliver the modern experiences partners and customers expect.

With Coherent Spark, those same spreadsheets become the backbone of governed applications. The logic you’ve already built is preserved, while the user experience finally catches up to what the business needs.

Why Old Paths Don’t Work

Leaders usually see two ways forward—and both are frustrating.

Option 1: Rewrite spreadsheets into custom software.

This route consumes already stretched development resources. It drags actuaries and product managers away from their day jobs, forcing them to translate models into code. It can take months—or years—before anything usable emerges. And by the time it does, the business logic has usually changed.

Option 2: Buy an off-the-shelf tool.

On paper, these platforms promise efficiency. In practice, they’re expensive, slow to configure, and rarely flexible enough to match the nuances of your models. Getting them up and running often takes longer than hoped, and tailoring them to fit your business logic is an uphill climb.

Neither approach respects the value already living in your spreadsheets.

These files aren’t temporary workarounds. They’re the distilled knowledge of your business—pricing formulas, actuarial tables, workflows—refined and trusted for years.

But locked in spreadsheets, that value can’t be scaled. And when growth, speed-to-market, and customer experience depend on faster systems, something has to give.

The better path doesn’t start with replacement. It starts with activation.

How Do You Turn Excel Into a Real App?

Coherent Spark takes your existing Excel file and turns it into API-ready code.

That’s the technical layer. But here’s what it means in practice:

• For actuaries and analysts: You keep working in Excel, with the same models you trust. No recoding, no translation. Spark makes your models instantly usable by other systems. Any updates you make flow straight into production apps.
• For underwriters and product teams: Instead of waiting for IT, you get usable apps built on the same models—complete with a front-end UI. No more emailing spreadsheets or rekeying data.
• For IT: You gain governance—version control, audit history, and approvals—without rebuilding everything from scratch. Integration with PAS, CRM, and other systems becomes clean and consistent.
• For leadership: You accelerate time-to-market, cut costs, scale new products and distribution without adding headcount, and enhance customer experiences. Weeks instead of quarters. Millions saved in rework.

Then, by pairing Coherent Spark with AI builders like Replit or Lovable, you go a step further.

The API generated by Spark feeds into AI prompts that can spin up a working front end in hours. What used to take months of custom dev now happens in a few days.

How Do I Turn an Excel Rating Model Into an Underwriting App?

Here’s how it works:

An insurer has a rating model in Excel. Historically, turning it into an underwriting workbench meant a full IT project: requirements gathering and scoping, recoding, integrations, testing.

With Coherent Spark, that model is converted into an API within minutes, not months. Then an AI tool like Replit can take the API’s Swagger file and generate a UI with a simple prompt:

“Based on this API swagger, please build a front end for a business user to easily interact with. I want it to operate like an underwriting workbench where users can save and retrieve quotes, as well as print them as PDFs.”

The result:

• An app that underwriters can use immediately.
• The ability to save, retrieve, and export quotes.
• Full fidelity to the original Excel logic.
• Delivery measured in days, not quarters.

That speed—going from a spreadsheet to a working underwriting app in less than a week—is what makes the power of Coherent Spark different.

Watch the demo:

TL;DR

So, if you've gotten this far, here’s what you need to know:

• Can you make an app from an Excel spreadsheet? Yes—with Spark, your file becomes an API that powers a real application.
• Can AI build a UI for Excel? Absolutely—Spark handles the logic, AI tools handle the interface.
• What business apps can you build this way? Time trackers, CRMs, billing systems, ticketing pipelines—and in insurance, rating engines, quote tools, underwriting workbenches, claims reserve tools, commissions calculators.
• Why not just rebuild or buy software? Because it’s slow, expensive, and ignores the IP already proven in Excel.
  
• What’s the impact? Faster product launches, more scalable processes, and apps your teams can actually use today.

Your spreadsheets already run the business.

Coherent Spark makes its logic usable at scale—so the models you trust become the systems everyone can use.