CSV to Excel

About this tool

Opening a CSV directly in Excel brings two classic nightmares: garbled Chinese text, and ID or order numbers turning into 3.7E+12. This tool fixes both at once - encoding is auto-detected (strict UTF-8 first, GB18030 as fallback for the most common exports), and long integers plus leading zeros are written as text so every digit survives.

The delimiter is sniffed automatically (comma / semicolon / tab) or can be forced; quotes are unescaped per RFC 4180. The output is a standard .xlsx you keep editing locally. Everything runs in your browser - customer lists and order data never leave the device.

Features

• Auto encoding detection: UTF-8 / GB18030 - no garbled text
• Long numbers and leading zeros written as text - no 3.7E+12
• Delimiter auto-sniffing or manual comma / semicolon / tab
• RFC 4180 parsing with proper unquoting
• Free, unlimited, local conversion - no upload

How to use

1. Drop or select the .csv / .txt / .tsv file
2. Pick the encoding (auto by default) and delimiter (auto by default)
3. Keep "long numbers as text" checked
4. Click Convert and download the .xlsx

Frequently asked questions

Why is my CSV garbled in Excel?

Encoding mismatch: UTF-8 bytes read as GBK or the reverse. The tool auto-detects - strict UTF-8 first, then GB18030 - or you can force an encoding.

My ID numbers turned into scientific notation - now what?

Excel renders numbers over 11 digits as floats. This tool writes 12+ digit integers and leading-zero values as text, keeping every digit exactly as in the file.

What about lost leading zeros?

Codes like 001 or 007 lose zeros when stored as numbers. With "long numbers as text" checked they are preserved verbatim as text.

Columns split wrong or quotes not removed?

Parsing follows RFC 4180 with automatic unquoting, and the delimiter is sniffed (comma / semicolon / tab) or can be forced. If splitting still fails, check for an unusual separator.

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