Free Online CSV to XLSX Converter

Or drag and drop your files here to upload.
A maximum of 20 files can be uploaded at once.

Please note: Your CSV file, once uploaded to our server will be deleted 15 minutes after upload so please download your converted CSV file before this time.

How to Convert your CSV to XLSX Online?

Here are 2 simple steps to convert your CSV to XLSX using our fast and free CSV converter tool.

Upload your CSV file

Click the "Upload a CSV File" button, then select a CSV to upload. The maximum file size is 100MB.

Download your XLSX

Click the download link to receive your XLSX file.

File format information for CSV and XLSX

ExtensionCSV
Full NameComma-separated Values
TypeDocument
Mime Typetext/csv
FormatText

The CSV format is a very simple general data format that has been around for many years and allows any text-based data to be stored and exchanged between systems that can interpret CSV files with minimal development needed.

Data is stored within the file as a series of columns separated by a ',' character. The simplistic nature of CSV files has made them a popular choice for exchanging data between spreadsheet applications such as Microsoft's Excel and databases such as the many SQL-based databases.

Support for CSV files is widespread amongst spreadsheet and database software, making it possible to import and export CSV from Excel and other spreadsheets. SQL databases also offer options to exchange data between CSV files.

ExtensionXLSX
Full NameMicrosoft Excel Spreadsheet
TypeDocument
Mime Typeapplication/vnd.openxmlformats-officedocument.spreadsheetml.sheet
FormatBinary

XLSX files have been around since the mid-2000's and are one of the most popular spreadsheet file formats available. It was created by Microsoft as a modern update to the existing Excel XLS file format, with the intention of making future improvements to the format easier to implement than the original XLS format.

Contained within an XLSX file is the spreadsheet data stored within XML files. The XLSX file itself is simply a compressed ZIP container, meaning the format allows for all the Excel assets, such as spreadsheet data, images, and charts, to be stored separately within a single file structure.

As well as being the native format used by Microsoft's Excel application, XLSX files can also be processed by other spreadsheet applications, and third-party conversion tools can easily interface with the XLSX file format.

Frequently Asked Questions

How can I convert my CSV file to XLSX?

First click the "Upload..." button, select your CSV file to upload. Your CSV file will be uploaded to our servers. When the CSV to XLSX conversion has completed, you can download your XLSX file straight away.

How long does it take to convert my CSV to XLSX?

We aim to process all CSV to XLSX conversions as quickly as possible, this usually takes around 5 seconds however this can be longer for certain files, so please be patient.

How accurate is the CSV to XLSX conversion?

We aim to provide the best conversion experience. Our tools are under constant review and development with new features being added every week.