Multi-File Hash Calculator
Calculate batch checksum hashes for multiple uploaded files simultaneously.
Base64 File Encoder / Decoder
100% Client-Side. Files never upload to any remote server.
About Multi-File Hash Calculator
The Batch Multi-File Hash Generator computes SHA-256, MD5, SHA-1, and SHA-512 checksums across dozens of files simultaneously, generating downloadable `checksums.txt` and `sha256sum` verification manifest files.
How to Use Multi-File Hash Calculator
Step 1
Select or drag-and-drop a folder or batch of files.
Step 2
Choose your target hashing algorithm (SHA-256 recommended).
Step 3
Review the batch hash calculation table.
Step 4
Click "Export SHA256SUMS" or "Download CSV".
Practical Use Cases for Multi-File Hash Calculator
Release Packaging & `sha256sum` Manifest Creation
Generate standardized `SHA256SUMS` manifest text files for open-source software releases and GitHub repository distributions.
Batch Integrity Auditing & Duplicate Discovery
Hash entire folders of photos, documents, or data backups to detect bit-rot and find identical duplicate files.
Input & Output Examples
Generating SHA256SUMS Manifest for 5 Files
5 binary release files uploaded
Downloadable `sha256sum.txt` containing `hash filename` pairs compatible with `sha256sum -c`
Key Features & Performance
- ✓Batch hashing of up to 1,000 files in a single session.
- ✓Generates standard Unix `sha256sum`, `md5sum`, and `sha512sum` manifest file formats.
- ✓Sortable table: sort files by name, size, or hash value with duplicate detection highlights.
- ✓100% Client-Side multi-threaded Web Worker execution.
- ✓1-Click Export CSV or `checksums.txt`.
Key Terminology & Definitions
`sha256sum` Manifest
A standardized text file listing SHA-256 hashes followed by filenames, used by Unix `sha256sum -c` to verify multi-file packages automatically.
Bit-Rot Detection
Detecting silent data corruption in archival storage by periodically comparing newly computed file hashes against original manifests.