About MergeExcel
MergeExcel was born out of a real frustration: I needed to merge dozens of Excel files at work, and every online tool I found had the same problem — they uploaded my files to their servers.
Since I was working with sensitive client data, I couldn't risk that information leaving my computer. The alternatives were: pay for desktop software I'd use once a month, or learn VBA macros (which sounded way more complicated than it should be).
Why Privacy First
This isn't just marketing. MergeExcel processes EVERYTHING locally in your browser using JavaScript. I literally have no way to see your files — they never even pass through my server.
You can verify this yourself: disconnect your Wi-Fi after loading the page, and you'll see the tool keeps working perfectly. That was the promise from day one.
How It Works (Technically)
We use the SheetJS library (XLSX.js), which runs entirely in your browser. When you select files:
- Your browser reads the files directly from your disk (FileReader API)
- JavaScript processes and combines the data in memory
- A new Excel file is generated
- You download it straight from your RAM — it never touched the internet
That's why it works offline, that's why it's instant, and that's why it's 100% private.
The Project Today
MergeExcel will always be free. Ads help cover hosting costs, but the tool is fully functional even with an ad blocker (I don't detect them or limit anything).
What's Next
I have a list of improvements based on real feedback:
- Support for more complex merges (automatic VLOOKUP across files)
- Filters and transformations before merging
- Better data preview
- Option to save configurations for recurring merges
If you have suggestions or find any bugs, drop me a line at hola@mergeexcel.es — I read every message.
Why trust me?
The code is open-source (you can view the JavaScript right in your browser).
No tricks, no invasive analytics, no login required. Just a tool that does what it promises.
- Jaume Sampol
Creator of MergeExcel