Supported file types: spreadsheets, text files, ZIPs and images
Which file extensions Content Uploader reads, how each is handled, what is refused, and the image types it can deliver, in one table.
- 2 min read
- Updated October 13, 2026
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Content Uploader recognises a file by its content, not by its name. The drop area offers these extensions; anything else is refused with The file field must have one of the following extensions: csv, tsv, txt, xlsx, xlsm, xls, ods, zip.
Spreadsheets and text files#
| Extension | What it is | How it is read |
|---|---|---|
.xlsx, .xlsm |
Excel workbook | First worksheet; macros are never run; formulas are read as the result last saved |
.xls |
Excel 97 to 2003 workbook | Converted to .xlsx first, in a separate step; a very large file can take half a minute or fail |
.ods |
OpenDocument spreadsheet (LibreOffice, Apache OpenOffice, Google Sheets download) | First sheet |
.csv, .tsv, .txt |
Text with separators | Comma, semicolon or tab, detected for you; UTF-8, or UTF-16 with a byte order mark |
.zip |
A ZIP of images, or one holding a spreadsheet and images | A ZIP alone must contain exactly one spreadsheet |
Refused#
| File | Message |
|---|---|
| Password-protected workbook | This workbook is password-protected. Remove the password in Excel and upload it again. |
.xlsb |
Excel binary workbooks (.xlsb) are not supported. Save it as .xlsx, .ods or CSV and upload it again. |
| Apple Numbers | Apple Numbers files are not supported. In Numbers, choose File › Export To › Excel or CSV. |
| A web page or XML saved as a spreadsheet | This file is a web page or XML document, not a spreadsheet. Open it in Excel, then save it as .xlsx or CSV. |
| Damaged or not a spreadsheet | This file is damaged or not a spreadsheet. Save it as .xlsx, .ods or CSV and upload it again. |
| A CSV that is not UTF-8 | Cells must contain valid UTF-8 text of at most 32 KB. |
.pdf, .docx, images and anything else |
The file field must have one of the following extensions: … |
Every message and its fix: the file cannot be read.
Images#
| Type | Accepted |
|---|---|
| JPEG, PNG, GIF, WebP, AVIF | Yes, further limited to what your site accepts |
| SVG | Never: SVG images are not accepted. Use JPG, PNG, GIF, WEBP, AVIF. |
| A web page or any other file | No |
Images reach Content Uploader in a ZIP next to the spreadsheet, from a web address in a cell, or from the site's own media library (where images come from). Sizes: limits.
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