Alchemy recommends using the CSV format for downloading large reports to ensure successful exports. This article explains the technical limitations of XLSX files and why CSV is the preferred format for large datasets.
Why XLSX Exports May Fail
Manager reports provide both CSV and XLSX export options, but very large reports, especially those with more than 500,000 rows, may fail to generate in XLSX format. This is due to technical limitations in Excel and the way XLSX files are processed. XLSX file generation is more resource-intensive than CSV, requiring significantly more memory and processing power, which increases the risk of timeouts or application crashes during export.
XLSX Limits and Practical Constraints
Excel’s hard row limit is 1,048,576 rows, but performance issues typically occur well before reaching this limit. Large reports with hundreds of thousands of rows and many columns:
- Take significantly longer to generate and open.
- Can cause Excel to freeze or crash.
- May exceed memory limits in your browser or on servers during file creation.
- XLSX exports require more processing power than CSV and are more likely to fail if they include formatting, formulas, or styles.
- Our current export system cannot reliably produce XLSX files of this size without risking timeouts or incomplete files.
Recommendation to Users
Because CSV files are:
- Faster to generate.
- More stable for large datasets.
- Compatible with Excel, Google Sheets, and most spreadsheet applications.
We recommend: use of CSV format to ensure successful downloads for large reports with more than 500,000 records.
Note: If your organization regularly generates reports with over 500,000 records, consider contacting your Account Manager for additional options.