From Excel Spreadsheet to Web Application
Your spreadsheet holds the real rules of your business. I turn it into a web application with users, permissions, history and reports, and I keep what already works.
Signs your spreadsheet has outgrown Excel
- Several people need to edit it, and copies of the file circulate by email.
- Nobody dares to change the formulas.
- Pivot tables and macros are rebuilt every time something changes.
- There is no history: you cannot tell who changed what, or when.
- Mistakes are found late, in a report or in an invoice.
- The file is slow, or too big to open comfortably.
What changes with an application
One source of truth
Everyone works on the same data, so there are no copies to reconcile.
Users and permissions
Each person sees and edits only what they should.
Validation and history
The rules live in the application, and every change leaves a record.
Reports without rebuilding
The reports and totals you build by hand today are produced by the application, and you can still export them to Excel.
How we turn a workbook into an application
- Understand the workbook I read the formulas, pivot tables and macros to find where the real rules live.
- Define a first version We agree on what moves to the application first and what can stay in Excel for now.
- Build and migrate I import your data and compare the totals with the spreadsheet, so both can be checked against each other.
- Run in parallel, then switch Your team uses both for a while, until the application proves it gives the same results.
If you want to define the scope before committing to a project, I also offer a one-week, fixed-price Discovery: a clear scope, a prototype and an estimate. Ask me about it.
I use AI-assisted development to deliver faster, and every change is reviewed and tested.
Experience
- Conciliación de Tarjetas started as one large Excel workbook with complex formulas and pivot tables. I turned it into a platform that automates the matching and verification of credit and debit card transactions.
- Independent consultant and developer since 2014: end-to-end software for small and medium businesses, startups and enterprise clients, from new web applications and REST APIs to database architecture. 40+ clients, 100+ projects and 4 proprietary SaaS products.
Frequently asked questions
Do I have to stop using Excel?
No. Excel is still great for analysis. The application takes over what needs several users, rules and history, and it can export to Excel whenever you need it.
Can you work from my current workbook?
Yes. The workbook is the best specification: I read its formulas, pivot tables and macros to find the real rules, and I confirm them with you before building anything.
What happens to my historical data?
It is imported into the new database. Before switching, I compare the totals with the spreadsheet, so you can see that both match.
How much does it cost?
It depends on the scope, so there is no fixed price list. Book a free 30-minute call and we will see what a sensible first version looks like.
Is your spreadsheet running the business?
Book a free 30-minute call and show me how it works today. We will see what a first version of the application could look like.