Steps to convert a CSV file
- Open the spreadsheet at gridcraft.run/editor.
- Drag the .csv file onto the grid (or choose Open… in the … menu of GridCraft’s title bar). .tsv and tab-delimited .txt files work the same way.
- Check the columns. The data lands on a sheet called Sheet1, one field per column.
- Tidy it up if you like: make the header row bold, freeze it (View › Freeze Top Row), turn the range into a table, sort, filter or add totals.
- Save. Click the Save button in the title bar or press Ctrl/⌘+S. The workbook downloads as an .xlsx with the CSV’s name:
orders.csvbecomesorders.xlsx.
How GridCraft reads a CSV
- Delimiter: comma, semicolon or tab, detected from the first lines (whichever splits every line the same way). Quoted fields may contain the delimiter, quotes (written twice) and line breaks.
- Encoding: UTF-8 and UTF-16 files with a byte-order mark, UTF-8 without one, and Windows-1252 (the encoding of older Excel exports) as the fallback, so accented letters come through.
- Values: read as if you had typed them.
1,000,$3,50%and(100)become numbers with a matching number format, dates such as1/2/2020become real dates, and TRUE and FALSE become logical values. Everything else stays text. - Formulas: a CSV holds values only, so a field such as
=A1*2is not calculated. Add formulas after opening.
Once saved, the .xlsx keeps what CSV can’t: number formats, column widths, several sheets, formulas, charts and tables.
Tips
- Combine several CSV files into one workbook by opening each one, copying its cells and pasting them onto a new sheet in the first.
- Paste instead of opening: tab-separated text copied from another app or a web table pastes straight into cells with Ctrl/⌘+V.
- Clean up messy exports with the Spreadsheet AI panel: attach the file and pick “Clean up data” to get a tidy table that opens as a new workbook.
- Save before closing the tab. The browser version has no autosave.
- Converting many files?
gridcraft-cli convert data.csv data.xlsxdoes the same from a script; see the desktop downloads.
FAQ
Is my CSV file uploaded during the conversion?
No. GridCraft reads the CSV and writes the .xlsx inside your browser tab. The file never reaches gridcraft.run’s servers.
My data uses semicolons. Does that work?
Yes. GridCraft looks at the first lines and picks comma, semicolon or tab, whichever separates every line consistently. Files saved by European versions of Excel, which use semicolons, open in columns.
Why did the leading zeros disappear from my codes?
GridCraft reads each value the way it reads typing, as Excel does: 00123 is a number, so it becomes 123. A value that starts with an apostrophe ('00123) stays text, so add one in front of such codes in the CSV if the zeros matter.
Can I convert XLSX back to CSV here?
Not in the browser: Save always writes .xlsx, and Export as CSV needs a file path, which only the desktop app has. The desktop app, or gridcraft-cli convert book.xlsx data.csv, writes CSV.
Is there a row limit?
GridCraft uses Excel’s sheet size, 1,048,576 rows by 16,384 columns, and stops reading a CSV at the last row. In practice the limit is the memory of your browser tab; files with hundreds of thousands of rows are more comfortable in the desktop app.