Merge Multiple Excel Files into One, Right in Your Browser

To merge multiple Excel files into one, select your reports, choose the worksheets you need, and review how their columns line up. CombineSheets processes the files in your browser. You can append records into one table or put each selected worksheet on a separate sheet in one XLSX workbook.

Start with a small pair of reports if you want to check the result before handling a larger batch. The synthetic January workbook and February CSV demonstrate different column orders, a new column, and a repeated record.

How to combine Excel files in three steps

Select your files and worksheets

Add XLSX, XLS, XLSM, ODS, or UTF-8 CSV files. File detection checks the contents, rather than relying only on the extension. Password-protected and encrypted inputs are rejected.

Check the worksheet selection in each workbook. Hidden worksheets start unselected, so a hidden notes sheet does not automatically enter your report. Include only sheets that belong in this particular result. Keep the original files for checking values later.

Choose a result and check the headers

Use One table when each input contains records of the same kind, such as monthly orders. The first non-empty row in each sheet becomes its header. Column names match regardless of capitalization or surrounding spaces; a changed column position does not change the match.

Use Separate sheets when you want one XLSX workbook containing the selected worksheets as individual sheets. This keeps their data apart, but it still exports values only. It does not preserve the original workbook's formatting or formulas.

Review the report and download

Before downloading, check rows read, empty rows skipped, duplicates removed, output rows, and new or missing columns for each sheet. Enable the optional Source file column if you need to trace records. Enable duplicate removal only when repeated whole rows should count once.

Download XLSX for a workbook result. CSV is available for one table; it cannot contain separate worksheets. Open the downloaded file and check a few records against your originals before using it for another task.

Combine Excel files with different column orders

Files with different column orders merge by matching header names; the first table sets the output order and later new columns are added at the end. These sample inputs show how that works:

Input	Columns in input order	Data rows
sales-january.xlsx, January	Order ID, Date, Region, Product, Units, Revenue	6
sales-february.csv	Region, Order ID, Date, Product, Revenue, Units, Sales Rep	6

January determines the initial column order. February's Sales Rep column is new, so it goes after Revenue. January has no Sales Rep values, so those cells stay empty. Here are the first rows of the combined table with Source file turned on and duplicate removal enabled:

Order ID	Date	Region	Product	Units	Revenue	Sales Rep	Source file
000101	2026-01-01	North	Notebook	1	12		sales-january.xlsx
000102	2026-01-02	South	Folder	2	24		sales-january.xlsx
…
000106	2026-01-06	West	Folder	6	72		sales-january.xlsx
000201	2026-02-01	North	Notebook	2	24	Taylor	sales-february.csv
000202	2026-02-02	South	Notebook	3	36	Taylor	sales-february.csv

February's first line repeats order 000101 with the same values and a blank Sales Rep, so it does not appear a second time.

The inputs contain 12 data rows. One February row repeats a January row exactly and has a blank Sales Rep cell. With duplicate removal enabled, the first copy stays, one duplicate is removed, and the result contains 11 data rows. The added source column is ignored when comparing duplicates.

Matching is based on names, not meaning. Revenue and Sales are different headers. Blank or duplicate header names stop the merge with a message, so correct those in the source before retrying.

What stays in the output

Cell values, leading-zero text IDs and Excel date formats stay in the output; formula expressions and other workbook formatting do not.

Item	Result
Cell values	Exported as values; empty cells remain different from zero
Text IDs with leading zeros	Kept as text, including IDs such as 000101
Excel dates	Kept as date cells in XLSX; readable date text in CSV and PDF
Formulas	Last saved values only; formula expressions are lost
Missing formula values	Export stops and asks you to recalculate and save
Fonts, fills, borders, column widths	Not preserved
Merged-cell layout, conditional formatting, validation	Not preserved
Comments, images, charts, pivot objects	Not preserved
Macros and external links	Not preserved

Formula cells keep their last saved values, so recalculate and save formula-based reports in your spreadsheet app before combining them. A saved formula value can be old even when the file opens successfully. Check the formula review guide if totals depend on other sheets or workbooks.

Local processing and practical limits

File contents, file names, sheet names, headers, and cell values stay in your browser. Account and payment connections are separate from file processing. Read the privacy details for the information used by those services and hosting.

Free batches allow 50 MB of total input across up to 30 files, with a merge and split guard of 1,000,000 non-empty cells. A pass raises these to 100 MB, 300 files, and 2,000,000 non-empty cells. Phones have 20 MB and 300,000 non-empty cells per batch across all tiers. Browser memory can still run out below these limits. See free limits and passes before planning a large run.

Continue with a specific task

You can combine Excel sheets by column name, join CSV reports, or split worksheets into individual files. For a reading copy of each worksheet, review separate PDF exports; these rebuild the values as tables rather than reproduce the original print layout.