Upload your Excel file (.xlsx, .xls) and download it as CSV. Clean your data during conversion: remove duplicates, validate emails, fix dates. 100% browser-based, no upload to servers.
Drop your .xlsx or .xls file. Files stay in your browser, never uploaded to servers.
If your Excel has multiple sheets, choose which one to convert. Preview data in clean table.
Select cleaning tools: duplicates, emails, dates, numbers, whitespace, and 9 more.
Click "Download CSV" to get your clean .csv file instantly. No server processing.
Excel files never leave your browser. No server upload, no cloud storage.
Remove duplicates, validate emails, fix dates – all in one step.
Convert 10,000+ rows in under 1 second. No waiting, no spinning wheels.
Once loaded, works in your browser even offline. No internet needed.
Import Excel data into databases, APIs, or data pipelines. CSV is the universal import format for MySQL, PostgreSQL, MongoDB, and most data tools. Clean data during conversion to ensure data quality.
Example: Client sends 20,000 product records in Excel → Remove duplicates → Clean price formatting → Download CSV → Import to MySQL database.
Convert Excel contact lists to CSV for import into Mailchimp, HubSpot, Salesforce. Validate emails, remove duplicates, and fix formatting issues before importing to avoid bounces and duplicates.
Example: Export Excel contact list → Validate 5,000 emails → Remove duplicates → Fix "gmial.com" typos → Download CSV → Import to Mailchimp.
Convert Excel survey results, research data, or analytics exports to CSV for analysis in R, Python, Tableau, or other data science tools. Clean and normalize data during conversion to save preprocessing time.
Example: Survey results in Excel → Normalize date formats → Remove empty rows → Trim whitespace → Download CSV → Import to Python/pandas for analysis.
Find and remove duplicate rows based on any column combination. Keep first or last occurrence.
Validate email syntax, fix common typos (gmial→gmail), flag disposable addresses.
Convert dates from 30+ formats to ISO 8601 (YYYY-MM-DD). Handle US/UK formats.
Trim leading/trailing spaces, remove double spaces, clean tabs and line breaks.
Remove currency symbols ($, €, £), normalize decimals, clean thousand separators.
Text case, split/merge columns, country codes, find & replace, filters, empty rows, and more.
Upload your Excel file (.xlsx or .xls) to neatcsv, optionally clean the data, and click "Download CSV". The conversion happens in your browser and is 100% free for files up to 10,000 rows (Starter plan, 9€/month). No installation required.
No. All Excel to CSV conversion happens in your browser using JavaScript. Your file never leaves your computer. This ensures maximum privacy and GDPR compliance.
Yes! If your Excel file has multiple sheets, neatcsv will let you choose which sheet to convert to CSV. You can preview each sheet before converting.
.xls is the old Excel format (Excel 97-2003), while .xlsx is the modern format (Excel 2007+). neatcsv handles both formats seamlessly. The output CSV is the same regardless of input format.
Yes. Excel formulas are automatically converted to their calculated values in the CSV output. This is the expected behavior since CSV doesn't support formulas.
File size depends on your plan: Starter (10k rows), Professional (100k rows), Business (500k rows). Processing happens in-browser, so very large files may require a modern browser with sufficient memory.
CSV is a plain-text format and doesn't support formatting (colors, fonts, borders, etc.). Only cell values are preserved. If you need to preserve formatting, keep a backup of the original Excel file.
Yes! neatcsv offers 14 cleaning tools: remove duplicates, validate emails, fix dates, clean numbers, trim whitespace, and more. Select the tools you need, preview the changes, then download as CSV.
Join thousands of users who trust neatcsv for data cleaning and conversion.
Start Converting Now