merge-json-files.com

Merge & Combine Excel Files Online

Combining multiple Excel workbooks into one report is a time sink. Instead of toggling between windows, drop your .xlsx or .csv files here and merge the cell values into one output. It’s useful for consolidating monthly reports or inventory lists without manual copy-paste.

Download Sample Excel Files to Practice

Sample Excel Files

Merge Strategies

Choose the right approach for your data

Merge strategy feature comparison
FeatureAppend RowsSeparate SheetsMerge by Header
When to UseFiles share the same column structureYou need data separated by source fileFiles have overlapping but different columns
Output StructureSingle sheet with all rows stackedOne sheet per source file in one workbookSingle sheet with a union of header names
Header HandlingUses first file headers, skips duplicatesEach sheet retains its own headersAligns rows into a unified header set
Best ForMonthly reports, survey batches, log exportsDepartment data, multi-source archivalMixed schemas, supplier catalogs, CRM exports

How It Works

Four simple steps

1

Load Workbooks

Upload multiple .xlsx or .csv files. Data is processed locally in your browser.

2

Select Merge Strategy

Stack rows vertically, combine as separate sheets, or align rows by matching header names.

3

Review Limits

Large workbooks are checked against browser size and ZIP-expansion guardrails before parsing.

4

Export Unified Excel

Download a clean .xlsx or CSV output with the merged cell values.

Programmatic Merge

Python & VBA

How to Merge Excel Files in Python

Merging Excel files in Python is efficient using the openpyxl or pandas library. With pandas, use pd.read_excel() to load each workbook, then pd.concat() to combine sheets. The ExcelWriter class lets you write multiple sheets to one output file. Choose library options carefully if you need to preserve formulas, formatting, charts, or pivot tables.

Pythonmerge_excel.py
import openpyxl
import glob

merged_wb = openpyxl.Workbook()
merged_ws = merged_wb.active
header_written = False

for filepath in glob.glob("*.xlsx"):
    wb = openpyxl.load_workbook(filepath)
    ws = wb.active
    for i, row in enumerate(ws.iter_rows(values_only=True)):
        if i == 0 and header_written:
            continue  # skip duplicate headers
        merged_ws.append(row)
        header_written = True

merged_wb.save("merged_output.xlsx")
print(f"Merged {len(glob.glob('*.xlsx'))} files successfully.")

How to Merge Excel Files with VBA

Merging Excel files with VBA (Visual Basic for Applications) gives you full control within Excel itself. Use Workbooks.Open() to load each file, then loop through sheets and copy them to a master workbook with Sheets.Copy. VBA is often a better fit when formulas, charts, pivot tables, or conditional formatting matter. This is ideal for users who need to merge files directly in Excel without external tools or programming languages.

VBAMergeWorkbooks.bas
Sub MergeWorkbooks()
    Dim FolderPath As String, FileName As String
    Dim DestWB As Workbook, SrcWB As Workbook
    Dim DestWS As Worksheet, SrcWS As Worksheet
    Dim LastRow As Long, NextRow As Long

    FolderPath = "C:\Reports\"
    Set DestWB = ThisWorkbook
    Set DestWS = DestWB.Sheets(1)
    NextRow = 2 ' Start after header row

    FileName = Dir(FolderPath & "*.xlsx")
    Do While FileName <> ""
        Set SrcWB = Workbooks.Open(FolderPath & FileName)
        Set SrcWS = SrcWB.Sheets(1)
        LastRow = SrcWS.Cells(SrcWS.Rows.Count, 1).End(xlUp).Row

        SrcWS.Range("A2:Z" & LastRow).Copy _
            DestWS.Range("A" & NextRow)
        NextRow = DestWS.Cells(DestWS.Rows.Count, 1).End(xlUp).Row + 1

        SrcWB.Close SaveChanges:=False
        FileName = Dir()
    Loop
    MsgBox "Merge complete!"
End Sub

FAQ

Common questions

Complete Guide

In-depth walkthrough

What this tool does

This tool combines multiple .xlsx or .csv files into one workbook. Each input file becomes a separate sheet in the merged output, or rows can be appended into one sheet depending on the merge mode you choose.

For normal tool use, file contents are processed locally in your browser instead of being uploaded for server-side merging. The page may still load site ads, analytics, and other third-party scripts described in the privacy policy.

It's completely free with no signup required. Just drop your Excel files in, click merge, and download the result.

Works with modern .xlsx files and .csv exports. If you have an older .xls workbook, save it as .xlsx first.

Merging sheets vs stacking rows - which mode to use

Use "merge as separate sheets" when each file has different data and you want to keep them organized in one workbook. For example, if you have monthly sales reports and want January, February, and March each on their own tab in one file.

Use "stack rows" when all files have the same column structure and you want one continuous dataset. This is perfect for export files from the same system, like combining weekly reports into one master list.

If your columns don't match exactly, use the Merge by Header option. Append Rows stacks columns by position, while Merge by Header creates a unified header set and fills blanks where a row does not have that column.

Most people use row stacking for identical file structures and separate sheets when the files contain different types of data.

Common problems when merging Excel files

Merged cells in the source files can cause unexpected row structure in the output. If you have cells merged across multiple columns or rows, unmerge them before uploading. In Excel, select the merged cells and click Unmerge Cells in the Alignment section.

Formulas referencing other sheets won't work after merging unless the referenced sheet is also in the output. For example, if Sheet1 has a formula =Sheet2!A1 but Sheet2 isn't included in the merge, you'll get a #REF error. The tool extracts calculated values, not formulas.

Files with password protection need to be unlocked before merging. The tool can't read password-protected Excel files. Open them in Excel, remove the password (File > Info > Protect Workbook > Encrypt with Password, then delete the password), save, and try again.

Very large workbooks can be slow or unsafe in the browser. The tool blocks oversized files and unusually compressed .xlsx files before parsing. For massive datasets, use Python with openpyxl or pandas instead of the browser tool.

If your merged file has weird blank rows or misaligned data, check that all source files have the same column headers spelled exactly the same way. Even a space or capitalization difference will create separate columns.

How to do this in Python if you need automation

If you need to merge Excel files automatically as part of a script or workflow, use Python with the openpyxl library. Install it with pip install openpyxl, then use openpyxl.load_workbook() to read files and append rows to a new workbook.

For data analysis, pandas is easier: pd.read_excel() to load each file, pd.concat() to stack them, then df.to_excel() to save the result. This handles column alignment automatically.

Both libraries handle .xlsx files, and pandas can also read legacy .xls files when the xlrd library is installed.

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