Does hashing upload the file?
No. The browser reads the bytes and uses its built-in cryptographic digest function locally.
- Browser-native cryptographic hashing
Guide
Verify file and folder integrity with the browser’s cryptographic API without uploading the selected contents.
Calculate a file checksum locally, or create and verify a SHA-256 manifest for an entire folder without uploading its contents.
Clear answers
Verify file and folder integrity with the browser’s cryptographic API without uploading the selected contents.
Calculate a file checksum locally, or create and verify a SHA-256 manifest for an entire folder without uploading its contents.
Does a matching hash prove a file is safe?
No. It proves the bytes match the expected checksum. If the expected value or original file is malicious, the hashes can still match.
- Create and verify deterministic folder manifests
Which algorithm should I use?
Use the algorithm published by the trusted source. SHA-256 is the most common default for modern file-integrity checks.
- Download output or save both manifests directly to a folder
Can I verify a whole folder later?
Yes. Save the generated JSON manifest, then choose it and the folder again to find changed, missing, added, or unreadable files.
A local check
Verify file and folder integrity with the browser’s cryptographic API without uploading the selected contents.
Calculate a file checksum locally, or create and verify a SHA-256 manifest for an entire folder without uploading its contents.
Selected file
Choose one file for a single checksum, or start a folder manifest from the batch integrity panel.
Choose one file for a single checksum, or start a folder manifest from the batch integrity panel.
Review before sharing
Create and verify deterministic folder manifests
For a file, select the trusted algorithm and optionally paste an expected checksum.
Local verification
For a folder, create new JSON and .sha256 manifests or choose an existing JSON manifest to verify.
For a folder, create new JSON and .sha256 manifests or choose an existing JSON manifest to verify.
Review every reported difference before downloading or saving the results.
Four local steps
Does a matching hash prove a file is safe?
- 01
Browser-native cryptographic hashing
Choose one file for a single checksum, or start a folder manifest from the batch integrity panel.
- 02
Create and verify deterministic folder manifests
For a file, select the trusted algorithm and optionally paste an expected checksum.
- 03
Download output or save both manifests directly to a folder
For a folder, create new JSON and .sha256 manifests or choose an existing JSON manifest to verify.
- 04
Browser-native cryptographic hashing
Review every reported difference before downloading or saving the results.
Browser privacy
SHA-256 File and Folder Checksum Calculator
Browser-native cryptographic hashing
No. The browser reads the bytes and uses its built-in cryptographic digest function locally.
Create and verify deterministic folder manifests
No. It proves the bytes match the expected checksum. If the expected value or original file is malicious, the hashes can still match.
Download output or save both manifests directly to a folder
Use the algorithm published by the trusted source. SHA-256 is the most common default for modern file-integrity checks.
Clear answers
Which algorithm should I use?
Use the algorithm published by the trusted source. SHA-256 is the most common default for modern file-integrity checks.
- A matching checksum verifies bytes, not whether a file is safe or trustworthy.
- The expected checksum or manifest must come from a trustworthy independent source.
- Folder processing is limited to 1,000 files, 2 GiB total, 250 MiB per file, and 20 folder levels.
Private workspace
SHA-256 File and Folder Checksum Calculator
Verify file and folder integrity with the browser’s cryptographic API without uploading the selected contents.