Do the chunks need to be in a specific naming format?

Yes, it expects the numbered chunk naming produced by the Large File Splitter (or a compatible tool) to reassemble them in the correct order.

What happens if a chunk is missing?

The file can't be reconstructed correctly without every chunk present — double check you have the complete set before joining.

Does joining verify the reassembled file is correct?

It reconstructs the file from the chunks provided; for extra confidence, compare a checksum of the result against the original if you have one.

Does File Joiner upload my files to a server?

No. File Joiner runs entirely in your browser using on-device processing, your files never leave your device.

File Joiner

Reassemble a file that was split into numbered chunks back into the original.

Runs in your browser

Drop file parts here

Choose File

Parts are joined in order by their part number and downloaded as the original file. Runs entirely in your browser.

About this tool

A file split into numbered chunks — whether by this platform's own splitter or another tool — is unreadable and unusable until it's put back together in the correct order. This tool reassembles those numbered chunks back into the original file exactly as it was before splitting, completing the other half of the split-and-transfer workflow.

Frequently asked questions

New

Large File Splitter

Split a large file into smaller numbered chunks for easier transfer.

Zip & Unzip Files

Combine files into a ZIP archive, or extract files from one.

File Size Converter

Convert between bytes, KB, MB, GB, and their binary (KiB/MiB/GiB) equivalents.

File Type Detector

Detect a file's true type from its byte signature, not just its extension.

Duplicate File Finder

Find identical files among a batch by comparing their content hash.

Batch File Renamer

Rename many files at once using a pattern, and download them as a ZIP.

File Extension Changer

Rename a file's extension without converting its actual format.

Hex Viewer

View the raw bytes of any file as a hex and ASCII dump.

File to Base64 Converter

Encode any file as Base64, or decode Base64 back into a downloadable file.

File Metadata Viewer

View a file's name, size, type and last-modified date.

GZIP Compressor

Compress or decompress a file using GZIP.

File Checksum Verifier

Verify a downloaded file against a published SHA checksum.

PDF Tools

Merge, split, compress and convert PDF files.

Image Tools

Compress, resize, crop and convert images.

Link & QR Tools

Shorten links and generate QR codes and barcodes.

Audio Tools

Convert audio files and turn text into speech, or speech into text.

Video Tools

Compress and process video files, right in your browser.

Developer Tools

JSON, encoding, hashing and text utilities for developers.

SEO & Web Tools

Meta tags, sitemaps, schema markup and other on-page SEO utilities.

Data & Spreadsheet Tools

Clean, convert and inspect CSV, TSV and tabular data.

Business Tools

Invoices, quotations, receipts and other business documents.

Social Media Tools

Resize images for social platforms, count hashtags and preview posts.