RowMergeBETA Files stay on your device
A LITTLE LESS SPREADSHEET WORK

Many CSVs.
One clean spreadsheet.

Merge CSV files by column name, even when the columns are in a different order. A few files in. One tidy file out.

✓ Free to use✓ No sign-up✓ No file uploads
FROM SCATTERED EXPORTS…
CSV january.csvCSV february.csvCSV march.csv
▦ merged.csv ✓ Columns aligned
NameEmailRegionAlex Morganalex@example.comWestSam Riverasam@example.comEastJordan Leejordan@example.comNorth
…TO ONE HAPPY TABLE ↗

Let’s bring your files together.

Runs in your browser

01 Add your CSV files

Drop your CSV files here

or choose a few from your device

CSV or TSV · UTF-8 · Up to 20 files, 10 MB each
    Your file contents never leave this browser.
    Columns, in the right placeMatched by header, not by position.
    Private by designNo file server. No account required.
    Less copy. Less paste.A single download, ready for your next step.
    A SMALL TOOL FOR A FAMILIAR TASK

    Three steps. One less thing on your list.

    01

    Choose your exports

    Add monthly reports, customer lists, or other CSV files with a header row. Comma, semicolon, tab, and pipe separators can be detected automatically.

    02

    Bring the columns together

    RowMerge matches column names, so “Email” stays under “Email” even if the column order changes. Keep all columns or require matching headers.

    03

    Check it. Download it.

    Preview the combined table, check the row count, and download a UTF-8 CSV. Open it in your spreadsheet app or use it in your next import.

    BUILT FOR EVERYDAY EXPORTS

    A fresh start for
    your scattered data.

    Combine January, February, and March reports. Bring regional contact lists together. Stack exports from the same system without moving columns around by hand.

    A NOTE ON HOW MERGING WORKS

    Rows are stacked. Columns are matched.

    This tool appends records from each file. It does not join records by an ID or update existing customers. A header named Email is different from email; leading and trailing spaces in headers are removed.

    Want exact copies removed? Turn on duplicate removal. The first occurrence is kept, and the source filename is excluded from that comparison.

    GOOD TO KNOW

    A few common questions.

    A little clarity before you merge.

    Can I merge CSV files with different columns?+

    Yes. “Keep all columns” creates a combined set of headers in first-seen order and fills missing values with blanks. If one file has Name and Email and another has Email and Region, the result has Name, Email, and Region. Use “Require matching columns” to catch missing or extra columns instead.

    Are my files uploaded or stored anywhere?+

    No file contents are sent to a server. Parsing, merging, and downloading happen in this browser tab. Clearing the files or closing the tab discards the tool’s in-memory copies. See our privacy information for details about hosting and optional usage analytics.

    Will leading zeros, quotes, and line breaks survive?+

    RowMerge keeps data as text, including leading zeros and quoted line breaks. Downloaded CSV fields are escaped as needed. Spreadsheet apps may still automatically convert values when opening a CSV; import identifier columns as text to keep values such as 00123. Formula protection may add an apostrophe to potentially executable cells in the download.

    What are the file and size limits?+

    You can add up to 20 UTF-8 CSV or TSV files, each up to 10 MB, with a combined limit of 30 MB and 100,000 data rows. A merged table can have up to 250 columns and 2 million data cells. Performance depends on your device. Excel workbooks (.xlsx) must first be exported as CSV UTF-8.

    How are duplicate rows identified?+

    Rows are compared after their columns have been aligned. Every data cell must match exactly, including case and whitespace. The source filename column is ignored for duplicate removal. This does not deduplicate by email, ID, or a single selected column.

    Why can’t a file be read?+

    Each file needs unique, nonempty column headers and valid CSV quoting. A row with more cells than its header is rejected; a shorter row is padded with blanks and reported. If separator detection is incorrect, choose it in import settings. For encoding errors, export the original file again as CSV UTF-8.