ExcelFusion Pro is a free, browser-based Excel merger tool that allows users to combine multiple spreadsheet files (.xlsx) securely in their browser without uploading any data to external servers.
Drop .xlsx files here or click to browse
Select two or more Excel files to merge and compare
Merged data will appear here
Traditional online Excel converters and manual copy-paste workflows introduce severe issues that slow you down and compromise security:
ExcelFusion Pro is a free, browser-based Excel merger. It processes all your files locally using JavaScript — no data is ever transmitted to a server. Here is what makes it powerful:
Upload and combine 2 or more .xlsx files simultaneously. Process massive spreadsheets locally without size limits or server time-outs.
Instantly match records across files using unique keys (like Roll or Name). ExcelFusion Pro intelligently aligns rows, combining overlapping fields with zero manual copying.
Filter and choose exactly which columns map to your output file. Clean up messy spreadsheets on the fly with responsive toggle chips.
All spreadsheet processing is sandboxed inside your local browser via SheetJS. Your sensitive financial, customer, or business data never touches an external server, meeting strict GDPR compliance.
Instantly download your merged and filtered dataset as a standardized .xlsx file, fully optimized and ready for immediate dashboard reporting.
ExcelFusion Pro is fully open-source on GitHub. Developers can inspect, audit, or clone the vanilla JS code to host a private copy on internal corporate intranets.
See how data analysts, finance managers, and developers use ExcelFusion Pro to simplify their workflows:
"ExcelFusion Pro saved me hours of manual copy-pasting. Being able to merge local sheets on client-side JS ensures my company's strict client privacy rules are never breached."
"The column-toggling chip system is exceptionally smooth. It allows me to trim down redundant headers and only merge what I need. Instant previews make debugging simple."
"As a developer, I love that this tool is fully open-source and respects local sandboxing. I audited the parser on GitHub and host a self-contained copy on our intranet."
How ExcelFusion Pro matches up against traditional methods for merging Excel files:
| Workflow Metric | ExcelFusion Pro | Excel Power Query | Python (Pandas) |
|---|---|---|---|
| Pricing / License | FREE FOREVER | Office 365 License | FREE (OPEN) |
| Setup Overhead | None (Drag & Drop in browser) | Built-in to Excel application | Python env & package install |
| Row Key Matching | Smart Automatic (Roll/Name match) | Manual Key Join configurations | pd.merge(on='key_column') code |
| Privacy Assurance | 100% Client-Side Local execution | Local desktop processing | Local script execution |
| Learning Curve | Zero (Instant GUI) | Medium (Advanced Excel skills) | High (Developer required) |
Consolidate your worksheets in seconds without running formulas or macros:
Drag and drop your spreadsheet files (in .xlsx format) directly into the secure upload zone, or click to browse files from your computer. You can upload two or more sheets at once.
If you anticipate empty cells in the merged outputs, define a fallback string (e.g. N/A or 0) in the configuration field. This ensures clean, uniform values across all rows.
Click the Merge & Preview button. The browser engine parses SheetJS logic to look for a matching column index (like Roll or Name) and merges rows. Toggle column chips to select which fields to output.
Search values instantly using filter fields in column headers. Uncheck individual rows you want to omit, then click Download Merged Excel to export your unified spreadsheet.
Automate Excel merging programmatically in your own pipelines or self-host a private microservice.
import pandas as pd
import glob
# 1. Load all .xlsx files in current directory
files = glob.glob("*.xlsx")
# 2. Merge using primary key alignment
dataframes = [pd.read_excel(f) for f in files]
merged_df = dataframes[0]
for df in dataframes[1:]:
# Match dynamically on 'Roll' or 'Name' keys
key = 'Roll' if 'Roll' in df.columns else 'Name'
merged_df = pd.merge(merged_df, df, on=key, how='outer')
# 3. Export to consolidated workbook
merged_df.to_excel("merged_output.xlsx", index=False)
print("Spreadsheets merged successfully via Python Pandas API.")const XLSX = require('xlsx');
// 1. Read input workbooks
const wb1 = XLSX.readFile('file1.xlsx');
const wb2 = XLSX.readFile('file2.xlsx');
// 2. Parse sheets to JSON arrays
const data1 = XLSX.utils.sheet_to_json(wb1.Sheets[wb1.SheetNames[0]]);
const data2 = XLSX.utils.sheet_to_json(wb2.Sheets[wb2.SheetNames[0]]);
// 3. Combine rows by matching key (Roll/Name)
const merged = [...data1];
data2.forEach(row2 => {
const match = merged.find(row1 => (row1.Roll === row2.Roll) || (row1.Name === row2.Name));
if (match) {
Object.assign(match, row2);
} else {
merged.push(row2);
}
});
// 4. Export output workbook
const newWb = XLSX.utils.book_new();
const newWs = XLSX.utils.json_to_sheet(merged);
XLSX.utils.book_append_sheet(newWb, newWs, 'Merged Data');
XLSX.writeFile(newWb, 'merged_output.xlsx');Self-Hosting Architecture Blueprint: Fast, Private, Scalable
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+---------------------------------------------+
| Client Web Browser SPA |
+----------------------+----------------------+
| HTTP POST /api/merge (multipart files)
v
+----------------------+----------------------+
| NGINX Reverse Proxy / API Gateway |
+----------------------+----------------------+
| Forward Request
v
+----------------------+----------------------+
| FastAPI / Node.js Merger Worker |
| (Offline parser using SheetJS/Pandas) |
+----------------------+----------------------+
| Read / Write Cache
v
+----------------------+----------------------+
| Redis In-Memory Data Store |
+---------------------------------------------+
Docker Setup Quickstart:
1. Dockerize a lightweight Python FastAPI / Node.js API container.
2. Bind Excel processing inside a Worker pool to offload large payloads.
3. Cache operations temporarily using Redis storage.
4. Route requests via NGINX with strict CORS constraints.ExcelFusion Pro operates entirely in your browser sandbox, ensuring absolute compliance with security rules:
All data parsing is executed on your CPU in memory. No files, metadata, or logs ever touch our hosting infrastructure.
Since data is never stored, indexed, or shared, ExcelFusion Pro complies directly with European GDPR and global data safety frameworks.
Our complete merging logic is open-source. Anyone can audit the repository on GitHub to verify our absolute privacy compliance.
No account setup required. Secure, browser-based merging, completely free.
Start Merging Now