SupportFree Online File Splitter - Split Large Files into Chunks
Split large files (JSON, CSV, TXT, etc.) into smaller, manageable chunks by size, lines, or structured records. All processing happens securely in your browser, outputting a zip file.
Splitting Options
Used for text/CSV splitting modes.
About the File Splitter Tool
Why use the BrainyTools File Splitter?
Working with extremely large files can be challenging, often leading to slow application performance or difficulties in sharing and processing. Our File Splitter tool allows you to break down these massive files into smaller, more manageable chunks, directly within your browser. This ensures your data remains private and secure, as nothing is uploaded to a server.
Key Features
- Multiple Split Modes: Split files by a specified chunk size (MB), by a fixed number of lines, or by a fixed number of records for structured data (CSV, JSONL).
- Wide Format Support: Compatible with JSON, JSONL, CSV, TXT, LOG, TSV, XML, NDJSON, and generic text files.
- Client-Side Processing: All file operations occur in your browser using Web Workers, ensuring privacy and a responsive UI.
- Zip Output: Download all generated chunks conveniently packaged in a single ZIP archive.
- Drag-and-Drop & Preview: Easy file upload with drag-and-drop, and a preview of file information before splitting.
- Header Row Preservation: For structured files, optionally maintain the header row in each split chunk.
How to Split Your Files
- Upload Your File: Drag and drop your file into the designated area or use the browse button.
- Choose Split Mode: Select whether you want to split by file size, number of lines, or number of records.
- Set Parameter: Enter the desired chunk size (e.g., 10 MB), lines per chunk (e.g., 1000), or records per chunk (e.g., 500).
- Configure Options: If splitting by records, decide if you want to maintain the header row.
- Split & Download: Click "Split File" and wait for the process to complete. Your chunks will be downloaded as a ZIP file.
Privacy and Performance
Our tool prioritizes your privacy and system performance. By leveraging Web Workers and streaming technologies, even very large files (up to 1 GB) can be processed without freezing your browser. Your data never leaves your device, providing a secure and efficient solution for all your file splitting needs.
Explore More Tools
Free Online Date & Time Converter | Timezone Aware
A professional, real-time date and time conversion utility. Instantly convert between Unix timestamps, ISO 8601, and human-readable formats across any global timezone. 100% client-side for maximum privacy.
Free Online JSON ↔ CSV Converter with Flattening
The ultimate tool to convert JSON to CSV and CSV to JSON. Features built-in support for flattening nested objects, custom separators, and smart column detection. Process large datasets securely in your browser.
Free Online JSON ↔ EXCEL Converter (XLSX) with Browser-Only Processing
Convert JSON to Excel (.xlsx) and Excel (.xlsx) to JSON in seconds. Supports nested JSON flattening, drag-and-drop uploads, and secure client-side conversion with no server upload.
Free Online JSON ↔ JSONL Converter with 5MB Safety Limit
Convert JSON to JSONL and JSONL to JSON instantly in your browser. Built for log pipelines and data engineering workflows with strict 5MB safety limits and private client-side processing.
Free Online Word & Character Counter
Welcome to the ultimate Real-Time Word and Character Counting Tool. Whether you are a professional writer, a student working on an academic essay, or an SEO specialist crafting meta descriptions, our tool provides the precision you need. Instantly track your progress as you type and ensure your content meets every specific requirement.
Free Online Text Case Converter
Our professional Text Case Converter is the fastest way to transform your writing into the exact format you need. Whether you are fixing accidental "CAPS LOCK" typing, preparing headlines for a blog, or formatting code strings, our tool provides a suite of transformation options to save you time and effort.
Free Online Find & Replace Text Tool
Our high-performance Find & Replace utility is designed for writers, developers, and editors who need a fast, reliable way to perform mass text substitutions. Whether you are updating a specific term across a large document or using Regular Expressions (Regex) for complex pattern matching, our tool provides a secure, browser-based solution for all your text manipulation needs.
Secure Online Base64 Encoder & Decoder
Our professional-grade Base64 utility provides a seamless way to convert text into Base64 format or decode existing Base64 strings back into human-readable text. Designed for developers and IT professionals, this tool operates entirely within your browser to ensure maximum privacy and security for your data.
Free Online JSON Formatter, Validator & Transformer
The ultimate developer tool to prettify, validate, minify, and transform your JSON data. Extract specific fields with lodash paths, remove sensitive keys, and merge multiple JSON files securely in your browser.
Latest Articles
JSONL Explained: The Unsung Hero of Modern Software Development 📄
JSONL (JSON Lines) is the stream-friendly data format powering AI datasets, log systems, and big data pipelines. Learn what it is, why it exists, and how to use it in Python and Node.js.
Why Hash Algorithms Quietly Power Security, Data Integrity, and Modern Software Systems 🛡️
From fingerprints to foundations, explore how hash functions ensure data consistency, security, and trust in the digital age.
Mastering String Manipulation in JavaScript 🔠
A deep dive into Uppercase, Lowercase, Title Case, and Sentence Case transformations with real-world examples.
The Hidden Superpower of Productivity: Why Find and Replace Is One of the Most Important Tools You’re Not Fully Using
Find and Replace is a foundational productivity engine for developers, analysts, and content teams. Learn practical use cases, regex workflows, and safe best practices.
Why Markdown (.md) Became the Language of Documentation
Markdown became the default documentation format because it is readable, version-control friendly, and easy to scale across engineering, data, and product workflows.