File Checksum Verifier
Compute a file's SHA checksum and verify it against a published hash, entirely in your browser.
Apa itu File Checksum Verifier?
A checksum (or hash) is a short, fixed-length fingerprint computed from a file's exact bytes — change even a single bit anywhere in the file and the checksum comes out completely different. Software vendors and download mirrors publish a checksum (usually SHA-256) alongside a file specifically so anyone downloading it can independently confirm the copy they received matches the original exactly, catching both accidental corruption (an interrupted or flaky download) and, to a meaningful extent, deliberate tampering. This tool computes a file's checksum locally in the browser using the Web Crypto API's SHA implementations, and optionally compares it against a checksum you paste in, so you don't have to manually eyeball two long hex strings character by character — the comparison also tolerates the inconsistent formatting (casing, whitespace, an "sha256:" prefix) that real published checksums often come in.
Cara menggunakan File Checksum Verifier
- Choose a file — anything from a downloaded installer to a document you want to verify hasn't been altered.
- Pick the hash algorithm the source published a checksum for (SHA-256 is the most common on modern download pages).
- The tool computes the file's actual hash locally and displays it.
- Paste the checksum the source published into the "expected hash" field — a clear match/mismatch result appears immediately.
Contoh
Verifying a download
Input: Downloaded installer.exe + the SHA-256 checksum from the vendor's download page
Output: Match — the file is byte-for-byte what the vendor published, not corrupted or tampered with
Mismatch caught
Input: A file that got corrupted mid-download, checked against the vendor's published hash
Output: Mismatch — signals a re-download is needed rather than trusting a possibly-broken file
Kesalahan umum
- Comparing against a checksum for the wrong file version or architecture (e.g. checking a 64-bit installer against the 32-bit build's published hash).
- Trusting a checksum from the same untrusted source as the file itself — a checksum only proves integrity (the file wasn't corrupted), not authenticity, unless it comes from a source you separately trust.
- Picking a different algorithm than the one the source actually published a checksum for — SHA-256 and SHA-1 hashes look superficially similar but will never match each other.
Mengapa menggunakan alat ini
- Verifies file integrity entirely client-side — no upload, works for large or sensitive files alike.
- Built-in comparison against an expected hash, not just a raw hash display you have to eyeball character-by-character.
- Tolerant of real-world checksum formatting (casing, whitespace, algorithm prefixes) instead of demanding an exact string match.
- Supports every algorithm the Web Crypto API implements (SHA-1/256/384/512) for whichever one a given source published.