Compare Known Hash (Optional)
Paste an expected checksum provided by a software developer or vendor. We'll clean whitespace and auto-detect length.
Drag & drop files here, or browse
SHA-256 and MD5 can process large files in chunks. SHA-384, SHA-512, and SHA-1 use whole-file browser memory and are limited to 256 MiB per file.
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Batch Checksum Verification
Paste a checksum manifest (e.g. SHA256SUMS, .md5, or CSV) then drop files to verify each filename with the algorithm implied by that manifest hash length.
Select or drop target files to match against manifest
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Passed (Match)
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Failed / Error
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Verification Audit Table
| Status | Filename | Expected Hash | Calculated Hash |
|---|
Understanding File Integrity & Cryptographic Hashes
A guide for both beginners and IT professionals on checksums, verification, and security boundaries.
1. What is a Cryptographic Hash?
A cryptographic hash function (like SHA-256) takes binary file data of any size and computes a fixed-length hexadecimal string (e.g. 64 characters). It acts like a compact fingerprint of the file contents. Different inputs can theoretically share a hash, so a digest is not a mathematically unique identifier.
2. Why are File Hashes Useful?
Hashes let you compare a local file with a trusted expected checksum without uploading the file. A mismatch detects that the bytes differ; a match is strong integrity evidence when the expected hash is trusted and the algorithm is appropriate.
3. What does a MATCHING Hash mean?
A matching hash (PASS) means the calculated digest equals the expected digest. With a trusted SHA-2 checksum this is strong evidence that the bytes match, but it does not by itself prove source authenticity or file safety.
4. What does a MISMATCH mean?
A hash mismatch (FAIL) means the calculated digest does not equal the expected digest. Causes can include different file bytes, an incorrect expected hash, or selecting/comparing the wrong algorithm.
Critical Security Distinction: Integrity ≠ Safety
Important: A checksum match does not prove a file is malware-free, authentic, or safe to run. If an attacker can replace both a file and the checksum you compare against, the values may still match. Obtain expected hashes through a trusted source and prefer modern SHA-2 algorithms for adversarial integrity checks.
Algorithm Quick Reference
| Algorithm | Hash Length | Status | Recommendation |
|---|---|---|---|
| SHA-256 | 64 chars (256 bits) | Modern SHA-2 | Recommended default for modern checksum verification when the expected digest comes from a trusted source. |
| SHA-512 | 128 chars (512 bits) | Modern SHA-2 | SHA-2 family option with a 512-bit digest; useful when a trusted source publishes SHA-512 checksums. |
| SHA-384 | 96 chars (384 bits) | Modern SHA-2 | SHA-2 family option with a 384-bit digest; useful when a trusted source publishes SHA-384 checksums. |
| SHA-1 | 40 chars (160 bits) | Legacy | Legacy only. Do not use when collision resistance or modern cryptographic protection is required. |
| MD5 | 32 chars (128 bits) | Legacy | Legacy only. Collision resistance is broken; do not use for adversarial security or authenticity decisions. |