Convert Case in Excel Files Online
Convert text columns to UPPERCASE, lowercase, or Title Case in Excel files directly in your browser. Apply case conversion to any or all text columns at once — no upload required.
How to convert Case in Excel files
- Drop your file onto the upload area. Every text column is ticked by default and the first 200 rows are shown.
- Choose the case type: UPPERCASE, lowercase or Title Case. One case type applies to every ticked column in a run.
- Adjust the columns under Apply to columns. Only text columns are listed. The All and None links tick or clear them all.
- Click Convert Case, check the preview, and download the file in the same format.
Your file is processed locally in your browser and is never uploaded. The free limit is 50 MB per file; larger files work if your device has the memory for them.
Worked example
Newsletter sign-ups were merged from two web forms, and email addresses arrive in mixed case. The mailing tool treats Jo.Bloggs@Example.COM and jo.bloggs@example.com as different contacts.
Input (Excel)
Excel workbook, first sheet (Sheet1)
| country | visits | |
|---|---|---|
| Jo.Bloggs@Example.COM | NZ | 3 |
| mika.k@example.fi | fi | 1 |
| ANNA.W@EXAMPLE.DE | DE | 7 |
| r.osei@example.gh | GH | 2 |
Settings
- Case type: lowercase
- Apply to columns: email only (country unticked; visits is a number and is not listed)
Result
| country | visits | |
|---|---|---|
| jo.bloggs@example.com | NZ | 3 |
| mika.k@example.fi | fi | 1 |
| anna.w@example.de | DE | 7 |
| r.osei@example.gh | GH | 2 |
Only the email column changes. Addresses that were already lowercase are left as they were. The country column was unticked, so "fi" is still lowercase. A second run with UPPERCASE and only country ticked would fix it. The visits column is a number and passes through unchanged.
Working with Excel files
Excel's UPPER, LOWER and PROPER need a helper column and a fill-down. Here the ticked columns are changed in place and written to a new workbook with plain values. The first sheet is read as displayed, so numbers shown with formatting, such as 1,200.00, arrive as text and are ticked by default. Converting them is harmless, because digits and punctuation have no case.
Case conversion is a common fix before VLOOKUP or XLOOKUP. Excel's lookup functions ignore case, but many databases and scripts do not. Converting the key column in both sheets means the same keys match everywhere. Formulas in the source sheet are read as their calculated values, so the output contains converted text, not formulas. Cell styles, column widths and other sheets are not carried over to the new .xlsx file. Only the first sheet is converted. Other sheets in the workbook are not read.
Frequently Asked Questions
Is this the same as Excel's UPPER and LOWER functions?
The result is the same, but you do not need helper columns or formulas. The ticked columns are replaced with converted plain values in the downloaded workbook.
Why are some Excel number columns ticked for case conversion?
Cells with number formatting, such as currency or thousands separators, are read as the text you see. They are harmless to convert, or you can untick them.
Can I apply different cases to different columns?
Not in one run. Each run applies one case type to all ticked columns. Run the tool again on the downloaded file with the other columns ticked.
Which columns can I convert?
Text columns only, and those are the only ones listed. Number, date and boolean columns have no letters to convert, so they are left unchanged.
Does it trim spaces or fix accents?
No. It only changes letter case. Accented letters are converted correctly, for example é to É, but spaces and punctuation are left alone. Use Trim Whitespace for spaces.
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