File Splitter

📖 Tool Introduction

File Splitter is a free online tool that cuts any file into several binary chunks of a fixed size. When you need to move a huge file across email attachments, cloud drives, USB sticks or chat apps, the transfer is often rejected for size; slicing it into parts, sending them in batches, and reassembling them at the other end restores the original exactly. The tool relies on the browser's native Blob.slice to perform zero-copy slicing without any transcoding or recompression, so splitting and merging back yields a byte-for-byte identical file and never corrupts data. You simply upload the file, choose a chunk size in KB or MB, and click Split; a list then appears showing every chunk with its sequence number, byte offset range, size and an individual download button. The last chunk is usually smaller than the chosen size, which is expected. A Download All button fires the downloads in chunk order so you do not have to click each row. Combined with the File Merger tool on the same site, you can pass large files safely between two machines. Because everything runs locally in browser memory, nothing is uploaded, which makes the splitter suitable for classified and private material as well. The slicing is instant even for gigabyte-scale files, since no bytes are re-encoded and no network is involved, so the tool also works fully offline. The generated names follow a predictable pattern such as file.part001, file.part002, which keeps chunks sorted automatically in most file managers. Whether you are mailing a big archive, copying a disk image onto small drives, or bypassing a chat size limit, the whole split-and-download flow takes seconds. A built-in example generates a deterministic 1.5 megabyte buffer so first-time visitors can watch a real chunk list appear without preparing their own large file. Because slicing never re-encodes bytes, the parts are identical to a command-line split on the same machine, which means the reassembled output is byte-for-byte the original even after thousands of miles between the two ends. The predictable part naming also plays well with the merger tool on the same site: upload the parts in natural sorted order and the rebuilt file matches the checksum of the source. The entire workflow needs no account, no upload and no installation, which makes it equally handy on locked-down work laptops and on slow hotel Wi-Fi.

✨ Key Features

• Zero-copy slicing: Blob.slice based, no transcoding or recompression
• Any file type: documents, installers, videos, disk images
• Free chunk size: KB or MB units, any positive number
• Chunk list: index, offset range and size shown for each part
• Single and batch download: per-part buttons plus Download All
• Local and safe: files stay in browser memory, never upload

📝 How to Use

1. Drop the file to split into the dashed box, or click to choose it
2. Enter the chunk size and pick KB or MB as the unit
3. Click Split now and wait for the chunk list to appear
4. Download each part, or use Download All to save them in order
5. To rebuild, use the File Merger tool and upload parts in order

⚠️ Notes

• Order matters: upload parts by part number when merging, a wrong order corrupts the file
• Chunk size: the chosen size only governs splitting; merging needs correct order
• Last chunk: the final part is smaller than the size, which is normal
• Batch download: browsers may block multi-downloads; click rows individually if needed
• Offline: slicing is instant and network-free, works even without connection