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Tool

Merge Multiple Files

Upload several Excel or CSV files whose columns are in different orders or under different names, match up which columns mean the same thing, and download one clean spreadsheet with a "Source File" column so you can trace every row back.

01 Upload your files

.xlsx, .xlsm or .csv, up to 10 MB each. At least two files.
Click to choose or drag files here
Nothing to merge yet?

02 Choose a sheet per file

Only shown for files with more than one sheet — the first sheet is used otherwise.

03 Match up the columns

Each row becomes one column in the merged file. Matches are suggested automatically — rename a row, reassign a cell, or add a new row for anything that shouldn't be merged in.

04 Preview and merge

Combine several spreadsheets into one, even when the columns don't line up

Monthly exports, regional reports, or files handed over by different people rarely share exactly the same column order or names — one calls it "Email", another "E-mail Address". Stacking them as-is either errors out or lines data up under the wrong header. This tool reads every file's real header row, matches columns that mean the same thing across files, and lets you confirm or correct that mapping before anything is combined.

How it works

  1. Upload two or more files. Each is read for its own header row and sheet list — a title row above the real header is handled automatically.
  2. Pick a sheet per file, if a file has more than one.
  3. Confirm the column mapping. Columns are grouped by how similar their names are once punctuation and case are stripped out, and you can rename, reassign, add or drop any row.
  4. Preview the merged result — row counts per file, anything skipped, and the first rows of the combined data.
  5. Download a single .xlsx with every file's rows and a "Source File" column recording where each one came from.

Columns that don't match become their own column

A column only one file has isn't dropped or forced into the wrong place — it becomes its own output column, blank for every file that doesn't have it. Nothing is merged that you haven't confirmed.

What people use it for

Common questions

What if a file is empty or won't open?

It's skipped, with the reason reported in the summary and the download's Summary sheet — the rest of the merge still goes ahead. A legacy .xls file falls in this category too; save it as .xlsx first and re-upload.

What happens to duplicate rows?

Nothing, unless you tick "Remove rows that are identical across files" — then a row whose mapped columns exactly match one already kept (from any file) is dropped, keeping the first copy seen.

Can I still tell which file a row came from?

Yes — every row in the merged file carries a "Source File" column with the original filename.

What are the file limits?

.xlsx, .xlsm and .csv, up to 10 MB each, up to 25 files a merge. Three merges a month without an account.

What happens to my files?

They're processed for your session and deleted within the hour. None are kept, shared, or used for anything else.