Professional CSV XLS converter online with advanced data protection for your Excel conversions. Leading zeros, phone numbers, international characters - all preserved with enterprise accuracy in both directions.
No registration required
Unlike basic CSV to Excel converters, we provide professional-grade data protection that prevents the 9 most common Excel corruption problems.
| Feature |
ConvertPro
|
Other Converters
|
|---|---|---|
| Data Protection Preserves leading zeros, phone numbers, currency | Full Protection | Basic/None |
| EU GDPR Hosting Data processed in European Union | Germany (EU) | USA/Mixed |
| Payment Model No monthly subscriptions | Pay-once | Monthly Subs |
| Registration Required Start converting immediately | No Signup | Required |
| File Auto-Deletion Privacy and security protection | Instant | 24+ Hours |
| Batch ZIP Processing Convert multiple files at once | Pro Plans | Limited |
Test the difference yourself: Try our CSV XLS converter online to see how we protect your data integrity, then check our pricing plans for higher limits.
Excel automatically converts data in ways that damage business-critical information. When your CSV files don't import correctly, here are the most common problems that affect data integrity.
ZIP codes, product IDs and account numbers lose critical leading zeros during Excel import, breaking identification systems
Credit card numbers, phone numbers and transaction IDs become unreadable scientific notation during Excel conversion
Precise decimal numbers get converted to unreadable scientific notation
Product codes, reference numbers and text data get auto-converted to dates, corrupting your records
International phone numbers lose structure, country codes and professional formatting
Financial data loses currency symbols, thousand separators and professional presentation
Non-ASCII characters become corrupted symbols, breaking international customer data
Dangerous formulas in CSV data can execute commands when Excel opens, creating security risks
Complex CSV with quotes inside quotes gets mangled, losing important text formatting
ConvertPro automatically detects and protects against all common Excel corruption patterns. Our CSV to XLS online conversion ensures your data stays exactly as you intended - every time.
ZIP codes, product IDs, account numbers maintain their zeros during Excel conversion. Applied text formatting prevents Excel from removing them.
Phone numbers, credit cards, IBANs stay in full readable format during Excel conversion. No more scientific notation confusion.
Scientific values keep their exact format and precision during Excel conversion. Research data stays accurate for analysis.
Text that looks like dates stays as text when intended during Excel conversion. Product codes and reference numbers remain unchanged.
International phone numbers keep their structure and readability during Excel conversion. Country codes and formatting maintained perfectly.
Currency symbols and number formatting preserved intact during Excel conversion. Financial data stays properly formatted and readable.
Polish, Russian, Chinese, Arabic - all characters preserved perfectly during Excel conversion. Proper encoding ensures international data integrity.
Dangerous formulas are neutralized and converted to safe text during Excel conversion. Your Excel files stay secure from malicious code execution.
Nested quotes and complex field structures handled expertly during Excel conversion. Even the most challenging CSV formats convert cleanly.
Everything you need to know about protecting your data
We prevent 9 types of Excel corruption: ZIP codes losing leading zeros (00123→123), phone numbers becoming scientific notation (4111111111111111→4.11E+15), international characters breaking (Kraków→Krak??w), currency formats disappearing ($1,234.56→1234.56), date auto-conversion (5-10→May 10th) and formula injection security risks. Your data stays exactly as intended.
Upload your CSV file and we automatically analyze it for Excel corruption patterns. We then generate a protected Excel file (.xlsx) with text formatting applied to vulnerable cells. This prevents Excel from auto-converting your data when opened, ensuring perfect preservation of leading zeros, phone numbers and international characters.
Yes. Your files are processed securely on our EU servers with enterprise-grade encryption and automatically deleted within seconds after download. We don't store, share or retain your data. Our privacy-by-design approach means no personal data collection or user tracking.
Yes. You can convert CSV to XLS free with all core data protection features and no hidden costs. No registration required, no credit card needed. Perfect for testing our advanced data protection quality before considering paid plans for bulk processing.
Currently 10 files per day while we develop our paid plans. This allows thorough testing of our advanced data protection across different file types and use cases. Each file can be up to 50MB with full data protection features included.
No installation required. ConvertPro works entirely in your web browser. Simply upload your CSV file and download the protected Excel file within seconds. Works perfectly on Windows, Mac and Linux with any modern browser.
We support CSV, TSV, TXT files for conversion to Excel (.xlsx) and Excel files (.xlsx, .xls) for conversion to CSV. Our bidirectional conversion includes advanced data protection in both directions, with automatic delimiter detection and encoding support.
Most conversions complete within 10-30 seconds depending on file size. Small files (under 1MB) process almost instantly, while larger files (up to 50MB) may take up to 2 minutes. You'll see real-time progress and analysis results during processing.
Yes, ConvertPro works on all operating systems including Windows, macOS and Linux. Since it's web-based, you only need a modern browser like Chrome, Firefox, Safari or Edge. The converted Excel files work perfectly with Microsoft Excel, LibreOffice and Google Sheets.
If conversion fails due to file format issues or corruption, we'll show you a clear error message explaining the problem. Failed conversions don't count against your daily limit. Most issues are resolved by ensuring your file uses standard CSV formatting with consistent delimiters.
Yes! Our CSV to Excel converter free plan allows 10 conversions daily with files up to 50MB. You can convert CSV to XLS online free without registration, and our CSV to XLS converter online free provides the same advanced data protection as our paid plans.
Our CSV XLS converter online provides advanced data protection that prevents 9 types of corruption, unlike basic CSV to Excel converters that often lose formatting. When you convert CSV to Excel online with ConvertPro, your leading zeros, phone numbers, and international characters stay perfectly preserved.
Our Excel to UTF-8 CSV conversion preserves international characters perfectly. When you use this conversion, Polish, Russian, Chinese, Arabic - all characters maintain proper encoding during conversion. We automatically detect and preserve UTF-8 encoding to ensure your international data stays intact and readable across all systems.
Convert CSV to Excel online or Excel to UTF-8 CSV - Choose your conversion type and upload your file
Convert CSV to Excel online with advanced data protection
Convert Excel to CSV with proper encoding and formatting
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