Batch File Hasher
Hash many files at once and export the manifest (TSV, JSON, or sha256sum).
How to Use
- Drop multiple files into the input area, or drop a folder (Chromium/Edge/Firefox support folder drops with preserved paths).
- Pick the hash algorithm: SHA-256 (recommended), SHA-1 (legacy), SHA-384, or SHA-512.
- Pick the export format: <strong>sha256sum</strong> (Unix-style, compatible with the sha256sum command), <strong>TSV</strong> (tab-separated for spreadsheets), or <strong>JSON</strong> (for programmatic use).
- Files are hashed in parallel; large files are streamed in chunks so memory stays bounded.
- Files are sorted alphabetically in the output for reproducible manifests.
- Click Download to save the manifest file.
| Name | Size | Hash |
|---|
Manifest formats
About the Batch File Hasher
The Batch File Hasher is a free tool for image, audio and file tasks. It runs right in your web browser, so there is nothing to download. Hash many files at once and export the manifest (TSV, JSON, or sha256sum).
How it works
Type in what you have, and the answer shows up right away. Change anything and it updates by itself. Everything runs in your browser, so it is fast and nothing you type is sent away.
Want the deeper story? The Knowledge Base explains the ideas behind the tools in more detail.
Frequently Asked Questions
Why generate a hash manifest?
<strong>Integrity verification</strong> — distribute the manifest alongside files so recipients can verify their copies are intact. <strong>Backup audit</strong> — compare manifests over time to detect bit-rot or unauthorized changes. <strong>Build reproducibility</strong> — capture exactly what you built so the same hashes prove identical output. <strong>Forensic chain-of-custody</strong> — establish that evidence files weren't modified during analysis.
What's the sha256sum format?
Unix convention: <code><hash> <filename></code> per line, double-spaced separator. Compatible with the <code>sha256sum -c</code> command on Linux/macOS to verify a manifest. The format is also accepted by Windows tools like <code>certutil -hashfile</code>. Hashes are lowercase hex; filenames are relative paths.
Will it handle large files?
Yes — files are read and hashed in chunks (typically 1 MB at a time) using the Streams API and Web Crypto. Memory usage stays bounded regardless of file size, so multi-GB files work fine. Total time scales with file size; expect ~1 GB/sec on modern hardware.
How do folder drops preserve paths?
Chromium-based browsers (Chrome, Edge) and recent Firefox support the WebkitGetAsEntry API for folder drops. Each file's relative path within the dropped folder is captured. The output manifest preserves these paths so you can verify the entire folder structure. Safari has limited folder-drop support.
Which algorithm should I use?
<strong>SHA-256</strong> for new uses — secure and universally supported. <strong>SHA-1</strong> only for compatibility with older systems (e.g., comparing against a SHA-1 manifest you didn't create). <strong>SHA-384</strong> for a truncated SHA-512 variant. <strong>SHA-512</strong> when you want extra collision-resistance margin or are matching SHA-512 manifests from other sources.
Are files uploaded?
No. Hashing happens entirely in your browser. You can hash sensitive files (private keys, source code, internal documents) without exposing them to any server.
How do I use the Batch File Hasher?
Just type your numbers. The answer shows up right away — there is no button to press. Change anything and it updates by itself.
Is it free? Does it work without internet?
Yes to both. It is free with no sign-up, and once the page has loaded it keeps working even with no internet.
Where does my data go?
Nowhere — every calculation runs on your own device. Nothing you enter is uploaded, logged, or stored.
Common Use Cases
Bulk file delivery verification
Generate a manifest before sending files; recipient verifies every file matches.
Backup integrity check
Compare manifests of a backup to its source — any mismatch indicates corruption or modification.
Software distribution
Publish SHA-256 hashes for all release artifacts so users can verify downloads.
Source code archival
Capture cryptographic fingerprints of release source trees for long-term archival.
Compliance documentation
Generate evidence-of-state manifests for regulatory or audit purposes.
Build reproducibility
Compare build outputs across time, machines, or contributors to verify reproducible builds.
Last updated: