Overview
Introduction
A published checksum only protects you if you actually check your download against it, which usually means opening a terminal and running a hashing command.
This tool does that check in your browser: upload the file(s), paste the expected checksum or listing, and see an immediate match or mismatch.
What Is Checksum File Verifier?
A real file-upload checksum verifier: it hashes the actual bytes of one or more uploaded files and compares each result against a pasted expected checksum or a full sha256sum/md5sum-style listing.
It's the checking counterpart to the Bulk File Hash Generator, which produces hashes; this tool verifies them against an expectation you already have.
How Checksum File Verifier Works
The pasted listing is parsed line by line into hash/filename pairs (or a single bare hash), matching the standard `<hex> <filename>` format hashing command-line tools produce.
Each uploaded file is hashed with the selected algorithm, matched to a listing entry by filename (or positionally, if there's exactly one file and one bare hash), and reported as a match, mismatch, or "no expected checksum found".
When To Use Checksum File Verifier
Use it right after downloading a file whose publisher provides a checksum, to confirm the download completed correctly and wasn't tampered with in transit.
It's also useful for confirming a backup or transferred copy of a file is byte-identical to the original, given its known hash.
Often used alongside Bulk File Hash Generator and SFV Checksum Verifier.
Features
Advantages
- Checks real file bytes against a real checksum listing format, not just pasted text.
- Accepts both a single bare hash and a full multi-file listing, so it works whether you have one file or several.
- Gives a clear match/mismatch/not-found verdict per file instead of just raw hash output to eyeball.
Limitations
- Each file is capped at 25 MB, the same limit as the Bulk File Hash Generator it shares its hashing logic with.
- Filename matching is exact (including case), so a listing using a slightly different filename than your local copy won't match automatically.
Examples
Best Practices & Notes
Best Practices
- Copy the expected checksum directly from the publisher's official page rather than retyping it, to avoid a transcription error producing a false mismatch.
- Double-check you selected the same algorithm the publisher used; a correct file with the wrong algorithm selected will also show as a mismatch.
- Treat a mismatch as a reason to re-download the file, not to ignore, since it can indicate either corruption or tampering.
Developer Notes
Reuses this category's `hashFiles()` function (shared with the Bulk File Hash Generator) for the actual hashing, then parses the listing with a regex matching the standard `<hex>\s+\*?<filename>` sha256sum/md5sum line format, falling back to treating the whole listing as one bare hash when there's exactly one file and one parsed entry with no filename.
Checksum File Verifier Use Cases
- Confirming a downloaded file matches a publisher's published checksum
- Verifying a backup or transferred file is byte-identical to its source
- Checking a full sha256sum-style listing against a local set of files at once
Common Mistakes
- Selecting the wrong algorithm for the pasted checksum's actual length, which produces a mismatch even for an otherwise-correct file.
- Assuming a "no expected checksum found" result means the file is bad; it usually just means the filename in the listing doesn't exactly match the uploaded file's name.
Tips
- If verification fails, check the digest length against the algorithm you selected (32 hex = MD5, 40 = SHA-1, 64 = SHA-256, 128 = SHA-512) before assuming the file itself is the problem.
- Filename matching is exact and case-sensitive, so when an entry reports "no expected checksum found", rename your local copy to match the listing rather than editing the hash in the listing.