Question 1

What is a file hash?

Accepted Answer

A file hash (checksum) is a fixed-size string computed from the file's contents. If even one byte changes, the hash changes completely. Hashes are used to verify file integrity — e.g. confirming a downloaded file matches the publisher's original.

Question 2

Which hash algorithms are supported?

Accepted Answer

SHA-256 (recommended), SHA-512, SHA-384, SHA-1 (deprecated), MD5 (deprecated), and CRC32 (non-cryptographic). All are computed simultaneously — no need to select one at a time.

Question 3

Can I verify a file against a known hash?

Accepted Answer

Yes. Paste the expected hash and the tool auto-detects the algorithm from the hash length (MD5=32, SHA-1=40, SHA-256=64, SHA-512=128 hex chars). You'll see a clear ✅ MATCH or ❌ NO MATCH banner.

Question 4

What extra features does this tool have?

Accepted Answer

10 extras: (1) All algorithms computed at once. (2) SHASUMS/checksum file parser. (3) Batch hash multiple files. (4) CSV/JSON export of batch results. (5) History (localStorage). (6) Hash format options (hex/upper/base64). (7) File comparison (are two files identical?). (8) Hash diff visualization (highlight differing chars). (9) HMAC mode with key. (10) Manifest generator for folder integrity.

Question 5

Is my file uploaded anywhere?

Accepted Answer

No. All hashing runs in your browser using WebCrypto (SHA family) and pure-JS implementations (MD5/CRC32). Your file never leaves your device.

Question 6

Why are MD5 and SHA-1 marked as deprecated?

Accepted Answer

MD5 and SHA-1 have known collision attacks — two different files can produce the same hash. They're shown for legacy compatibility (many old checksum files use them) but should not be used for new integrity verification. Use SHA-256 or SHA-512 instead.

File Hash Checker

How to use