How to open a CSV with more than 1 million rows
Excel can’t show more than 1,048,576 rows on a sheet (about 10.5 lakh), and anything past that is left out, often without a warning. To see every row, open the file in MegaCSV: it has no row limit and runs in your browser.
Why rows go missing
The row limit is part of Excel’s file format. A CSV can be any length, so a file with 3 million rows loses 2 million of them when Excel opens it. If you then save, those rows are gone from that copy.
Fix it with MegaCSV
- Drop the file on MegaCSV. Rows appear while the rest is read; the status line shows the true count, for example “3,204,118 rows · 14 columns”.
- Use Go to row to jump anywhere, Find to search all rows, and Filter to narrow them down.
- Export: as CSV (an exact copy of the matching rows) or as Excel, split into files that each fit in a sheet.
Other ways to fix it
- Power Query + Data Model (Excel for Windows) for pivot tables on all rows.
- Split the CSV into parts of 1,048,575 rows.
- A database or Python if you’ll query it every day.
Questions
Does Excel warn me when rows are missing?
Not always. Sometimes it shows “too large for the Excel grid”, but often the sheet simply ends at row 1,048,576. Compare the row count with the source to be sure.
How many rows can MegaCSV open?
There's no row limit. We've tested 192 million rows (20 GB). The practical limit is your computer.
Can I get all the rows into Excel?
As several files: MegaCSV's Excel export splits at 1,048,575 rows per file, with the header on each.
Do I need Power Query?
No. MegaCSV opens the file directly, with no formulas or setup.
Related
Facts checked November 2, 2026.