Excel Won't Open Your Merged CSV File
You need to combine multiple CSV files, but Excel throws an error: "File not loaded completely" or just truncates your data at row 1,048,576.
We've Been There
You're not doing anything wrong. Excel has a hard limit of 1,048,576 rows (about 1 million). If your combined CSV files exceed this, Excel will either:
- •Silently truncate your data (losing everything after row 1,048,576)
- •Show an error message and refuse to open the file
- •Crash or freeze when you try to merge files within Excel
This happens all the time with sales reports, analytics exports, CRM data dumps, and log files. You're combining data from multiple months or locations, and suddenly you're over the limit.
What Doesn't Work
Trying to open in Excel anyway
Excel will truncate at 1,048,576 rows. You lose data without warning.
Power Query or VBA scripts
Still hits the same row limit when loading the final result.
Online CSV tools with file size limits
Most have upload limits of 10-50MB and fail on large datasets.
Installing Python or command-line tools
Requires technical setup. Not practical for quick one-off tasks.
The Fix
Merge your CSV files in your browser. No Excel. No row limits. No installation.
How It Works
Our tool processes CSV files entirely in your browser using JavaScript. Because it doesn't rely on Excel's engine, there's no 1 million row limit. The only limit is your computer's available memory.
Privacy: Files never leave your computer. All processing happens locally in your browser. No upload to servers.
After merging: The merged CSV can be opened in tools designed for large datasets - Python pandas, R, PostgreSQL, MySQL, or split into smaller chunks for Excel if needed.
Try It Now - Free Forever
Merge your CSV files without Excel's row limit. No signup, no installation, completely free.
Merge CSV Files