How it works
The CSV to Excel converter imports a .csv (or .tsv) file and saves it as a properly formatted .xlsx spreadsheet — with correct column types, date detection, number formatting, and header row styling. Use it when you receive CSV data and need to open and edit it in Excel with proper formatting.
Opening a CSV directly in Excel via double-click often produces all-text columns, broken date formatting, and missing number formatting. The correct workflow — File → Import → Text Import Wizard — requires multiple steps. This tool produces a properly formatted .xlsx in one click.
How to use it: upload a .csv file. Configure the import: delimiter (auto-detect or specify), character encoding (UTF-8, Latin-1, Windows-1252), whether the first row is a header, and date format hint (MM/DD/YYYY vs. DD/MM/YYYY for ambiguous dates). The tool detects column types (numeric, date, text) and applies appropriate cell formatting. Click Convert and Download .xlsx.
Column type detection: numeric columns get number formatting, date columns get date formatting (dates display as dates, not numbers), text columns get plain text formatting. Detected types can be overridden per column.
Formulas: CSV files contain only values — no formulas. The .xlsx output contains the raw values only. If you need formulas, they must be added manually in Excel.
Privacy: CSV-to-XLSX conversion runs in the browser using SheetJS.
Frequently Asked Questions
- The auto-detect algorithm analyzes the first few rows, counts occurrences of candidate delimiters (comma, semicolon, tab, pipe), and selects the one with the most consistent column count. Auto-detection is correct in 95%+ of cases. Override it manually in settings if the auto-detection is wrong.
- Specify the date format in the Date Format setting (MM/DD/YYYY, DD/MM/YYYY, or YYYY-MM-DD). The tool then parses date columns and formats them as Excel date cells. Without specifying the format, ambiguous dates (01/02/2024 — is that January 2 or February 1?) may be parsed incorrectly.
- Yes. After uploading, the column type preview shows detected types. Click any column header to override its type: Text (no conversion), Number, Date, Boolean. Setting a column to Text prevents numeric-looking data (like ZIP codes '01234') from being stripped of their leading zero.
- Yes. The .xlsx output has AutoFilter applied to the header row — click the dropdown arrow on any column header in Excel to filter by value or sort ascending/descending. This is the standard spreadsheet behavior for imported data tables.