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Free Online File Hash & Checksum Verifier

Compute the MD5, SHA-1, SHA-256 and SHA-512 checksum of any file and verify it against a published hash — entirely in your browser. Files are never uploaded to a server.

This tool runs entirely in your browser. Your file is read locally and never uploaded, stored, or logged on any server.

Drop a file here

or click to browse — processed locally, never uploaded

Computing checksums…

Computed Checksums

Checksums are computed with the Web Crypto API (SHA family) and a local JavaScript implementation of MD5. No network request is made while hashing your file.

What Is a File Checksum?

A checksum (or hash) is a short, fixed-length fingerprint generated from a file's exact contents. Changing even a single bit in the file produces a completely different checksum, which makes hashes a reliable way to verify that a downloaded or copied file is identical, byte for byte, to the original. Software publishers routinely publish the SHA-256 or MD5 checksum of a release next to the download link so users can confirm the file was not corrupted in transit or tampered with by a third party — a use case related to, but distinct from, our hash generator, which creates a hash from typed text rather than a file.

Common Uses for Checksum Verification

Checksum verification is a routine step in several everyday and professional workflows:

Verifying a downloaded ISO, installer or archive matches the checksum published by the software vendor.

Confirming a backup or transferred file is a byte-for-byte copy with no corruption.

Establishing chain-of-custody evidence in digital forensics, where an unchanged hash proves a file was not altered.

Checking that a firmware or dependency package has not been tampered with before installing it.

MD5, SHA-1, SHA-256 or SHA-512: Which Should You Use?

For integrity verification against accidental corruption (a failed download, a bad disk sector), MD5 and SHA-1 are still fast and perfectly adequate, which is why many older software releases still publish MD5 checksums. However, both are cryptographically broken and unsuitable wherever a malicious actor could deliberately craft a file with a matching hash — for that, use SHA-256 or SHA-512, which remain collision-resistant and are the current standard for security-sensitive verification. This tool computes all four so you can match whichever one the publisher provided.

Frequently Asked Questions

No. The file is read locally with the browser's FileReader API and hashed with the Web Crypto API (for SHA-1/256/512) and a local JavaScript MD5 implementation. No network request is made — you can verify this by opening your browser's developer tools and watching the Network tab, or by disconnecting from the internet after the page loads.

A mismatch almost always means the file is genuinely different from the original — corrupted during download, incompletely downloaded, or modified. Double-check you copied the full expected hash without extra spaces or line breaks, and that you are comparing the same algorithm (MD5 vs. SHA-256 hashes look similar in format but are completely different values).

SHA-256. MD5 and SHA-1 have known collision vulnerabilities, meaning a determined attacker can theoretically construct two different files that share the same hash. For simple accidental-corruption checks either works fine, but whenever integrity against tampering matters, prefer SHA-256 or SHA-512.

Yes, within the memory limits of your browser and device — the whole file is read into memory once to compute all four checksums in parallel. Very large files (several gigabytes) may take longer and use more RAM, but everything still happens locally with no upload involved.

The hash generator hashes text you type or paste directly into a box. This tool hashes the raw bytes of an actual file selected from your device — the input method differs, but both use the same underlying algorithms and are equally private and client-side.