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Merge Excel Files Online - Free

Merge Excel files online free — combine multiple XLSX, XLS, CSV, ODS, XLSM, XLSB or TSV files into a single workbook directly in your browser. Choose Append Rows, Preserve Sheets, or Side-by-Side Columns. No upload, no signup, no install — instant download.

Processed entirely in your browser No spreadsheet data sent to servers Optional duplicate row removal No signup required Works on desktop and mobile

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XLSX · XLS · XLSM · XLSB · CSV · TSV · ODS

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Merge Mode

Append Rows

Stack all rows into one sheet. Smart column alignment handles different headers automatically.

Preserve Sheets

Each file (and all its sheets) becomes a separate tab in the output workbook. Data is never mixed.

Side-by-Side Columns

Place files horizontally next to each other - ideal for comparing data sources in parallel.

Remove duplicate rows Remove identical rows after merging

Output Format

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How To Merge

How to Merge Excel Files Online in 3 Steps

Add your files, pick a merge mode, and download one combined spreadsheet in XLSX or CSV. The whole process runs in your browser — no upload, no install, no Excel required.

Add Your Spreadsheet Files

Drag and drop, or click Browse Files, to add the Excel and spreadsheet files you want to merge. Supported input formats: XLSX, XLS, XLSM, XLSB, CSV, TSV, and ODS. Mixed formats are supported in the same merge — combine Excel workbooks and CSV exports together without converting them first. There is no upload step. Files are read directly in your browser.
Choose Your Merge Mode

Pick the mode that matches the structure of your files. Append Rows stacks every file's rows into one continuous sheet — best when files share columns, such as monthly reports or recurring exports. Preserve Sheets keeps every sheet from every file as separate tabs in one workbook — best when each file is a distinct dataset. Side-by-Side Columns places each file's data in parallel column blocks — best for visual comparison of two or more Excel files. You can switch modes any time before clicking Merge & Download, and you can optionally remove duplicate rows before downloading.
Merge & Download in One Click

Click Merge & Download. Your files are read, parsed, and combined entirely on your device, then the merged workbook downloads directly to your Downloads folder — XLSX (recommended) or CSV. No queue, no email link, no waiting on a server. Typical merge time: under 5 seconds for ten files of normal size.

Why teams use this merger

Save time when merging recurring reports and exports.
Reduce manual copy-paste mistakes between files.
Keep merged data organized in one clean output file.

Merge Modes

Choose the Right Merge Mode for Your Files

Pick the mode that matches your spreadsheet structure, then export as XLSX or CSV.

Append Rows

Best when all files represent the same dataset. Rows from each file are stacked into one sheet, and columns are aligned by header name.
Preserve Sheets

Best when you need each workbook and sheet to stay separate. Every sheet from every file is kept as its own tab in one output workbook.
Side-by-Side Columns

Best for side-by-side comparison. Data from the first sheet of each file is placed in parallel column blocks in one sheet.

All three modes produce a standard XLSX workbook or CSV file as output. The merger auto-aligns columns by header name in Append Rows mode, so files with the same columns in different order still combine cleanly. Files with different schemas can still be merged in Preserve Sheets mode — each file becomes its own tab. Use Side-by-Side Columns when you need to read two files next to each other rather than combine their data.

Quick mode comparison

Quick mode comparison
Mode	Best for	Input sheets used	Formulas/formatting
Append Rows	Stacking similar tables	First sheet from each file	Not preserved in the same way
Preserve Sheets	Keeping workbook tabs separate	All sheets from every file	Sheets are carried over
Side-by-Side Columns	Comparing files next to each other	First sheet from each file	Not preserved in the same way

Different Columns

Merge Excel Files With Different Columns and Headers

Use Append Rows mode when your files share some fields but not the exact same layout.

Columns are aligned by header name, so column order can differ between files.
If a file is missing a header that appears in other files, those cells remain blank.
This mode is useful for combining exports from different teams, systems, or reporting periods.
Use optional duplicate row removal after merging when files may contain overlapping records.

Supported Formats

Supported Spreadsheet Formats — XLSX, XLS, CSV, ODS, XLSM, XLSB, TSV

Every common spreadsheet format is supported as input, and you can mix any combination of them in a single merge. Output as XLSX (full Excel workbook) or CSV (flat file for data tools).

Merge XLSX Files Online (Excel 2007 and later)

XLSX is the modern Excel format used by every workbook from Excel 2007 onward. Multi-sheet XLSX files are read in full — merge mode determines whether all sheets are preserved or only the first.

Merge XLS Files Online (Legacy Excel 97-2003)

Older XLS files from Excel 97 through 2003 are accepted as input without re-saving to XLSX first. Output is XLSX or CSV.

Merge XLSM and XLSB Files (Macro-Enabled and Binary)

Macro-enabled XLSM files and binary XLSB files are accepted as input. Worksheet data is merged; macros (VBA code) are not executed and are not carried into the output — only the data values and sheet structure.

Merge CSV and TSV Files Online — No Upload

Comma-separated (CSV) and tab-separated (TSV) files are first-class inputs. Combine multiple CSVs into one Excel workbook, or merge CSV and XLSX together in one operation. Output as CSV to feed downstream data tools, or as XLSX for human review.

Merge ODS Files (OpenDocument / LibreOffice)

ODS is the OpenDocument Spreadsheet format used by LibreOffice and Apache OpenOffice, and a common export format from Google Sheets. Merge ODS files directly — or mix them with XLSX, XLS, and CSV in the same merge operation.

Mix Formats in One Merge

You do not have to convert formats before merging. Drop an XLSX, two CSVs, an ODS, and an XLSM into the file list and the merger reads them all. Mixed-format merging is the fastest way to consolidate exports from different tools — CRM as CSV, finance system as XLSX, survey tool as ODS — into one workbook.

Output as XLSX or CSV

Two output choices. XLSX is the right output when you want a single Excel workbook for most use cases. CSV is the right output when you need a flat data file for ETL pipelines, BI platforms, or further scripting in Python or R.

Private Processing

Merge Excel Files Without Uploading Them

This is a browser-based Excel merger designed for private, on-device processing. If your files contain anything sensitive — financial records, customer data, employee information, internal pricing — the difference between a server-upload tool and a browser-based one is the difference between trust and risk.

100% client-side. The merge runs in JavaScript in the same browser tab you are reading right now. Files are read into local memory using the standard FileReader API, parsed in-browser, combined, and written to a new file that downloads directly. There is no HTTP upload, no S3 bucket, and no temporary server storage.
No signup, no email gate, no account. The merge tool works the moment the page loads. The merge flow never collects your name, email, file names, or file contents.
Works offline after the first load. Once the page has loaded once, the merge keeps working even if your connection drops. The first page load needs a connection; after that, the merge itself runs locally.
Safe for sensitive spreadsheets. Browser-based processing is what makes this tool appropriate for files you would not put on someone else's server — finance team account exports, HR rosters, and compliance audit data. The privacy model is the same as opening the files in Excel on your own laptop.

Use Cases

When to Merge Excel Files — Common Use Cases

The merge modes look abstract until you map them to a real workflow. These are the most common reasons people land on this page.

Merge monthly reports from multiple branches.
Twelve monthly sales reports, one workbook per branch, same column layout. Drop them in, choose Append Rows, hit Merge & Download. One continuous sheet you can pivot or filter.
Combine sales exports from different tools.
Different reps export from different tools — CRM as CSV, finance as XLSX, a survey workflow as ODS. Mixed formats merge in one operation, and duplicate-row removal helps clear repeated records.
Unify supplier or vendor lists.
Procurement holds a master list, and each business unit maintains additions. Append Rows aligns by header, while Remove duplicate rows helps clean the inevitable repeats.
Consolidate survey or form exports.
Three regions, three Google Forms, three separate ODS exports. Combine them into one workbook for analysis without installing LibreOffice or reformatting every file first.
Prep data for analysis in Excel, Power BI, Python, or R.
Most analysis starts with consolidation. Merge your raw exports here, export as CSV for data tools or XLSX for workbook review, and move on without spending the morning on manual prep.

Comparison

Browser-Based Merger vs. Other Ways to Combine Excel Files

Several tools merge Excel files. Here is an honest, side-by-side comparison of the most common alternatives.

Comparison of browser-based Excel merger versus other options
Feature	This tool (browser-based)	Online merger (server-upload type)	Excel Power Query	Desktop merger software
Install required	No	No	Excel required	Windows install
Files uploaded to a server	Never	Yes (server-side merge)	n/a (local)	n/a (local)
Signup or email gate	None	Often email-gated	None	License key
Cost	Free	Daily limits or paid tiers	Microsoft 365 license	Paid software
XLSX, XLS, CSV, ODS in one merge	Yes	Varies by tool	Complex setup	Yes
XLSM / XLSB input	Yes	Varies	Yes	Yes
Append, Preserve Sheets, Side-by-Side modes	All three	Usually one	Setup required	Varies
Optional duplicate removal	Built-in	Rarely	Manual step	Varies
Works offline after first load	Yes	No	Yes	Yes
Time to merge 10 typical files	~5 seconds	30-120 seconds	5-10 minutes setup	10-30 seconds

vs. Online server-upload mergers

Many online Excel mergers upload your files to a remote server, process them there, and keep them off-device during the merge. For non-sensitive data that may be acceptable. For files you would not email to a stranger, browser-based is the better fit because the privacy guarantee is a technical fact, not a policy promise.

vs. Microsoft Excel Power Query

Power Query is powerful, but it also has a learning curve. To merge a folder of files you need Excel installed, the right version, consistent table structure, and several setup steps. For one-off or occasional merges, a browser tool is faster. For automated, repeatable, monthly-refresh data pipelines, Power Query is the better long-term choice.

vs. Downloadable Excel merger software

Standalone desktop mergers are usually paid Windows utilities. They merge files locally and handle very large batches well. The tradeoffs are installation, license keys, Windows-only support, and the up-front cost. For an occasional consolidation job, a free browser tool covers most of those use cases without the friction.

When to use which

One-off or occasional merge, especially with sensitive data -> browser-based (this tool).
Scheduled, repeatable, refreshable data pipeline in a corporate environment -> Power Query.
Very large enterprise batch jobs on Windows -> desktop merger software.
Quick merge of non-sensitive public data with no privacy concern -> any online tool works.

Before You Merge

Before You Merge — A Quick Checklist

Five quick checks before you hit Merge & Download.

Remove file protection first. Password-protected, encrypted, or DRM-locked spreadsheets are not supported. Open the file in Excel, save without a password, then merge.
Pick the matching mode. Append Rows is best for same-shape data, Preserve Sheets keeps everything intact, and Side-by-Side Columns is best for visual comparison.
Order your file list before merging. Output order follows the order in which files appear in the list. Drag to reorder before clicking Merge & Download.
Know what gets preserved. Preserve Sheets keeps source formulas and formatting. Append Rows and Side-by-Side Columns flatten formulas to values and strip cell formatting.
Large files use browser memory. A few hundred MB of input is usually fine on a desktop. If your browser stalls, close other tabs and try again with fewer files at a time.

FAQ

Frequently Asked Questions

Is this tool free to use?

Yes. MergeExcelFilesOnline.com is free to use and does not require signup. Add your files, choose a merge mode, and download the result.

What file types are supported?

You can merge XLSX, XLS, XLSM, XLSB, CSV, TSV, and ODS files. Mixed file types are supported in the same merge.

What is the difference between Append Rows, Preserve Sheets, and Side-by-Side Columns?

Append Rows stacks rows from the first sheet of each file into one table and aligns columns by header. Preserve Sheets keeps all sheets from all files as separate tabs in one workbook. Side-by-Side Columns places data from the first sheet of each file next to each other in parallel columns.

What happens if my files have different columns?

In Append Rows mode, columns are matched by header name. Column order can differ, and missing values are left blank where a file does not contain a header.

Can I merge workbooks with multiple sheets?

Yes. Preserve Sheets mode keeps all sheets from every input file. Append Rows and Side-by-Side Columns use the first sheet from each file.

Will formulas and formatting be preserved?

In Preserve Sheets mode, original sheets are carried into the output workbook. In Append Rows and Side-by-Side Columns, data is converted into merged row-and-column tables, so source formulas and cell formatting are not preserved in the same way.

Are password-protected files supported?

Password-protected or encrypted spreadsheet files are not supported for merging. Remove file protection first, then merge the files.

Is it safe to merge sensitive spreadsheet files?

Files are processed in your browser on your device, and spreadsheet data is not uploaded to our servers. For sensitive files, still use a trusted device and browser environment.

Can I merge Excel files without uploading them?

Yes. The merge process runs in your browser, so spreadsheet contents are not uploaded to our servers by the tool.

Can I combine CSV and Excel files?

Yes. You can merge CSV and Excel formats together, including XLSX, XLS, XLSM, XLSB, and ODS, then export the result as XLSX or CSV.

Which merge mode should I choose?

Choose Append Rows for one combined table, Preserve Sheets to keep each sheet as separate tabs, and Side-by-Side Columns when you need file data aligned next to each other for comparison.

Can I merge two Excel files into one sheet online for free?

Yes. Add both files using drag and drop, select Append Rows mode, and click Merge & Download. The two files become one continuous sheet in the output XLSX. The whole process is free, runs in your browser, and requires no signup.

How do I merge 3 (or more) Excel files into one workbook?

Drop all the files into the file list, choose a merge mode — Append Rows for one combined table, Preserve Sheets for separate tabs in one workbook — and click Merge & Download. The number of files does not change the workflow. Three files, ten files, fifty files all work the same way.

What is the difference between merging Excel files here and using Power Query?

Power Query is a built-in Excel feature for repeatable, refreshable data pipelines — the right tool when you will run the same combination every week and want it to auto-refresh. This merger is the right tool for one-off or occasional merges where you just want a combined file once, without the Power Query setup. Both approaches are valid; pick the one that matches your workflow.

Does the merge work offline?

After the page has loaded once, yes. The merge runs in JavaScript in your browser tab, so it keeps working even with no internet. The first page load needs a connection; after that, the merge itself is fully offline.

Is there a file size or file count limit?

There is no fixed limit imposed by the tool. The practical ceiling depends on your browser and device memory — on a typical desktop, merging a few hundred MB of input across many files works fine. If the browser stalls on very large jobs, close other tabs and try again with fewer files at a time.