CSV text workbook

A workbook that treats every value as text

CSV files contain text and separators, but they do not carry spreadsheet cell types. A spreadsheet may interpret an identifier such as 00123 as a number, or turn a date-like value into a date. This tool creates an XLSX workbook with explicit text cells. It helps you carry the text that is still present in your CSV into a spreadsheet without asking the spreadsheet to guess each cell’s type.

How to use it

Choose a local UTF-8 or BOM-marked UTF-16 CSV file, or paste comma-separated text, with a header row and at least one data row. Choose Create text workbook, inspect the preview, then choose Download text-data.xlsx. Open the downloaded file in a spreadsheet application that supports XLSX. Every cell, including the header, is text. If you need arithmetic or date calculations afterwards, deliberately convert only the columns you want to use that way.

Try an example

Choose Load example and create a workbook. The code 00123 should still show its two leading zeros. The long reference 123456789012345678 stays an exact text identifier. The value 03-04 stays those five characters. The value =1+1 is written as literal text rather than as a spreadsheet formula. The report counts several patterns worth checking, but all values receive the same text-cell treatment whether or not a pattern is flagged.

CSV rules and limits

Use commas between fields. Put a field in double quotes when it contains a comma, a newline or a quote; write a quote inside that field as two quotes. Each record must have the same number of fields as the header. A single final line ending is allowed. Empty cells, duplicate headers and spaces are preserved. Direct file import preserves the decoded file's quoted CRLF, CR and LF cell line endings. The textarea shows an editable view, whose displayed line endings are normalized to LF by the browser; conversion keeps using the original imported text until you edit that view. Editing any text switches conversion to the textarea value, including its LF line endings. The source-status message tells you which path is active. Pasted text also uses LF line endings. The preview shows at most six rows and five columns; the workbook includes every parsed cell.

The tool accepts up to 1,000,000 input characters, 5,000 data rows and 100 columns. Each cell must fit Excel’s 32,767-character limit. Unsupported XML control characters, invalid Unicode and literal Excel escape sequences such as _x0041_ are rejected with an explanation. Files may be valid UTF-8 (with or without a UTF-8 byte-order mark) or UTF-16 little-endian or big-endian with the matching byte-order mark. The source message identifies the selected decoding path. Files are limited to 4 MiB before decoding; the same character, row and cell limits still apply. Malformed text is rejected without replacement characters. UTF-16 without a byte-order mark, UTF-32 and legacy Windows encodings are not supported; re-export those sources as CSV UTF-8 first. Encoding support does not change the delimiter: tab-separated Unicode text still needs a comma-separated export. This version accepts comma-separated text, not semicolon-delimited files, existing spreadsheets, formulas, styling or macros.

What it cannot restore

If another application has already removed leading zeros or rounded an identifier before you copied the CSV, this tool cannot reconstruct the missing characters. Check the original text first. The warning counts are examples, not a complete prediction of every spreadsheet’s import behavior. Text numbers do not automatically participate in calculations. Saving this workbook back to CSV removes its explicit cell types; opening that CSV later can cause the same guessing problem again.

Your data and the download

Parsing, preview and workbook creation happen in this page’s memory. There is no account, upload, persistent browser storage or remote conversion service. Choosing a file reads it only in this page; a failed read clears the previous source and cannot leave an old workbook ready to download. Choosing a different file replaces the current text, and Clear also cancels any pending read. Editing the input removes the previous result and download link; create the workbook again after a change. Clear removes the input and result. Reloading or closing the page discards its temporary state. A file you choose to download remains on your device until you delete it. Test a small sample in your spreadsheet application before relying on a larger workbook.