ZIP codes keep their zeros and long IDs stay whole.
Free for 10 runs a day.
Every ZIP code keeps its zero
Excel reads 02134 as a number and drops the zero. Long IDs turn into 1.21E+10. Saving back to CSV makes the loss permanent.
This converter stores those columns as text in the Excel file.
Semicolons and accents open right
European exports separate columns with semicolons. Excel puts each whole row in column A. José opens as José.
The separator is detected and every name reaches Excel spelled right.
Use it from a script or an AI agent
MCP https://dedupe.ly/tools/mcp every free tool in one connector (this one: csv_to_excel)
POST https://dedupe.ly/tools/api/csv-to-excel
{ "csv": "ZIP,Phone\n02134,+12125550123", "format": "xlsx" }
Docs https://dedupe.ly/tools/api/openapi.jsonQuestions about converting CSV to Excel
Choose the CSV file or paste its rows, pick .xlsx or .xls and press Convert. The Excel file downloads straight away.
No. The conversion runs in your browser and the file never leaves your computer.
Excel reads a column of digits as a number, and a number has no leading zero. This converter writes any value that starts with 0 as text, so 02134 stays 02134.
Excel keeps 15 digits of a number and shows the rest in scientific notation. Values longer than 15 digits, or starting with a plus sign, are written as text and stay whole.
Yes. Comma, semicolon and tab files are detected and split into columns.
Yes. Pick .xls for Excel 97 to 2003. An .xls sheet holds 65,536 rows and 256 columns at most.
No. Dates and codes such as 3-4 or MAR1 are written exactly as they appear in the CSV.
Yes. Tick the option to keep numbers as text too, and Excel shows every cell exactly as the CSV has it.
Yes. Ten conversions a day, free.
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Scott B
VP Platform Ecosystem, HubSpot
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