Excel crashes. Uploading sensitive data isn't an option.

Handle CSVs Excel Can't Open
Without Uploading Your Data

25+ browser-based tools for splitting, merging, cleaning, and converting CSV and Excel files up to 10M+ rows. All processing happens locally. No servers involved.

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Popular tools:CSV Splitter|CSV Merger|Data Cleaner

View performance benchmarks →

Watch: 2M rows split in 2.62 seconds – 100% local processing

10M+

Row Capacity

Handle files Excel can't

25+

Tools

CSV & Excel processing

100%

Private

Zero data uploads

10s

Avg Process Time

Seconds, not minutes

Common Use Cases

Split Large CSVs

Break 10M+ row files into chunks in seconds (tested: 10M rows in 28s).

Merge Files

Combine millions of rows without servers (tested: 15M rows in 67s).

Aggregate & Group

SQL GROUP BY for non-coders. Count, sum, average 10M+ rows (tested: 10M rows in 18s).

Clean Data

Fix formatting issues, remove empty rows, trim whitespace (tested: 10M rows in 23s).

Remove Duplicates

Clean datasets by removing duplicate rows based on any column combination.

Convert Formats

Transform between CSV, TSV, Excel, and JSON with encoding and delimiter control.

Extract Columns

Pull specific columns from large files, reorder fields, or create subsets of your data.

Excel crashes at 1M rows. Google Sheets freezes. Paid tools require uploads.

SplitForge processes files directly in your browser, without uploads or servers. Your data stays on your device.

How It Works

Your File

Select CSV or Excel

↓

Browser Processing

SplitForge runs locally

↓

Processed File

Download result

Uses browser APIs (File, Streams, Web Workers). All processing happens locally. Works offline. No data transmission.

Why Browser-Based Matters

Complete Privacy

No uploads, no servers, no tracking. Your data never leaves your device.

Massive Scale

Process files with 10M+ rows that crash Excel and Google Sheets.

Verified Performance

Tested at 351K rows/sec. Real benchmarks, not marketing claims.

No Setup Required

No installs, no accounts, no limits. Just open and use.

Built for Professional Data Work

Enterprise-Scale Processing

Handle datasets that crash desktop apps. Tested with files containing 10M+ rows and gigabytes of data.

10M+ rows

Absolute Privacy Guarantee

Your data processes entirely in your browser. No uploads, no servers, no cloud processing. GDPR compliant by design.

Zero uploads

Professional-Grade Performance

Real benchmarks show 351K rows/sec processing speed. Optimized algorithms handle complex operations efficiently.

351K rows/sec

Zero Vendor Lock-In

Works offline, no account required, no subscription needed. Your workflow stays independent and portable.

Always available

Start Processing Securely

No signup. No uploads. No credit card. 25+ tools ready to use right now.