Group Concatenate Excel Files Online
Concatenate text values within each group in Excel files directly in your browser. Group rows by a column and join the values of another column into a single delimited string — no upload required.
How to group Concatenate Excel files
- Drop your file onto the upload area. The first 200 rows are shown so you can check the columns loaded correctly.
- Pick a Group by column, or leave it on "No grouping (whole file)" to join every value into a single cell.
- Choose the column to concatenate values from, then set the separator (", " by default) and the output column name ("values" by default). Type \n in the separator for a new line or \t for a tab.
- Optionally pick a column under "Order values within group by" and a sort direction, so the joined values come out in a predictable order.
- Click Concatenate Values, check the result, and download it in the same format you uploaded. The file has one row per group.
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
A blog CMS exports one row per article and tag. The editor wants a single row per article with all its tags in one cell, sorted alphabetically, to paste into a content audit.
Input (Excel)
Excel workbook, first sheet (Sheet1)
| article_slug | tag | added_by |
|---|---|---|
| csv-vs-parquet | parquet | mia |
| csv-vs-parquet | csv | mia |
| json-basics | json | raj |
| csv-vs-parquet | file-formats | omar |
| json-basics | apis | raj |
Settings
- Group by: article_slug
- Concatenate values from: tag
- Separator: ", "
- Order values within group by: tag, Ascending
- Output column name: tags
Result
| article_slug | tags |
|---|---|
| csv-vs-parquet | csv, file-formats, parquet |
| json-basics | apis, json |
Five rows become two, one per article. Only the group column and the new tags column are kept, so added_by is dropped. Tags are sorted A to Z inside each cell because tag was chosen as the ordering column. The output rows themselves are sorted by article_slug. Without an ordering column, the tags would still be joined, but their order inside each cell is not guaranteed.
Working with Excel files
Only the first sheet is read, and each cell is read as the text Excel displays. A price cell showing "$1,200.00" is joined as "$1,200.00", not as 1200. That is often useful here, because the joined cell reads the same as the original sheet. Formula cells contribute their last calculated value, not the formula. Date cells are the exception. They load from their stored value, so a date shown as 3/2/26 is joined as 2026-03-02, and ordering by that column follows the calendar. Dates typed as text still sort as text, so 10/1/26 comes before 9/30/26. Merged cells hold their value only in the top-left cell, so the other rows of a merged group label are empty and form a separate group.
An Excel cell can hold at most 32,767 characters. If one group has thousands of values, the joined text can pass that limit and Excel may cut it off or refuse to open the file. Split very large groups first, or download from a CSV or Parquet page instead. The downloaded .xlsx has a single sheet named Sheet1 with one row per group, and the joined cells are plain text. With \n as the separator each value sits on its own line in the cell. Turn on Wrap Text in Excel to see them.
Frequently Asked Questions
Is there a limit on how long the joined text can be in Excel?
Yes. Excel allows up to 32,767 characters per cell. Groups with many long values can exceed it. Check the longest groups in the preview before downloading.
Which sheet of the workbook is grouped?
The first sheet only. Extract another sheet with the Excel Sheet Extractor first if the data you need is elsewhere.
Which columns are kept in the output?
Only the group-by column and the new concatenated column. Every other column is dropped, because the result has one row per group. With no grouping, the output is a single row with a single column.
Are NULL values included in the joined string?
No. NULLs are skipped. If every value in a group is NULL, the joined cell for that group is NULL rather than an empty string.
Can I use a newline as the separator?
Yes. Type \n in the separator box and each value goes on its own line. \t inserts a tab. To join with a real backslash, type \\ for each backslash you want.
Related Tools
Split Column in Excel Files Online
Split a column into multiple columns by delimiter in Excel files directly in your browser. Turn "First Last" into separate first and last name columns — no upload required.
Find & Replace in Excel Files Online
Find and replace text values in Excel files directly in your browser. Supports plain text and regex patterns across any column — no upload required.
Sort Excel Files Online
Sort Excel files by any column, ascending or descending, directly in your browser.
Group Concatenate CSV Files Online
Concatenate text values within each group in CSV files directly in your browser. Group rows by a column and join the values of another column into a single delimited string — no upload required.
Group Concatenate Parquet Files Online
Concatenate text values within each group in Parquet files directly in your browser. Group rows by a column and join the values of another column into a single delimited string — no upload required.
Group Concatenate JSON Files Online
Concatenate text values within each group in JSON files directly in your browser. Group rows by a column and join the values of another column into a single delimited string — no upload required.
Excel Viewer Online
View and inspect Excel files directly in your browser. Browse rows, check column names and data types — no upload required, your data stays on your device.
Convert Excel to Parquet Online
Convert Excel files to Parquet format directly in your browser. No upload required — your data never leaves your device.