Frequently Asked Questions
How do I generate a hash from text or a file?
Type or paste your text, or upload a local file, then pick an algorithm — MD5, SHA-1, SHA-256, SHA-384, or SHA-512 — and the digest appears instantly in your chosen format (hex or Base64). You can paste an expected hash to verify a match, then copy or download the result. Everything happens in your browser; nothing is uploaded.
Does this upload my data, and does it work offline?
No upload, and yes it works offline. All hashing happens in your browser using the built-in Web Crypto API (and an in-page routine for MD5) — there's no server receiving your text or files, no logging, and no tracking. That matters when you hash a private file or string. Once the page has loaded it keeps working with no internet connection.
What's the difference between MD5, SHA-1, SHA-256, and SHA-512?
They're different hash algorithms producing different-length digests. MD5 is 128-bit and SHA-1 is 160-bit — both fast but cryptographically broken. SHA-256, SHA-384, and SHA-512 are part of the SHA-2 family and produce 256, 384, and 512-bit digests respectively, and remain secure. For a fingerprint you want to trust against a determined attacker, use SHA-256 or larger; MD5 and SHA-1 are fine only for casual integrity checks.
Can I decrypt or reverse a hash?
No — hashing is a one-way function by design. There's no key and no inverse: you cannot compute the original input from its hash. Sites that claim to "decrypt" a hash are really just looking it up in a precomputed table of common inputs (like leaked passwords), which only works for weak, well-known values. For any real input, the hash is irreversible, which is exactly what makes hashing useful.
Which algorithm should I use?
For anything security-sensitive, use SHA-256 (or SHA-384/SHA-512) — they're the current safe default. Use MD5 or SHA-1 only for non-security tasks like a quick checksum to catch accidental corruption, where speed matters and an attacker isn't in play. And remember: for storing passwords, no fast hash is appropriate — use a slow key-derivation function such as bcrypt, scrypt, or Argon2 instead.
Are MD5 and SHA-1 safe to use?
Not for security. Both are cryptographically broken: practical collision attacks exist, meaning an attacker can craft two different inputs with the same hash. That makes them unsafe for digital signatures, certificates, password hashing, or anything an adversary could exploit. They remain perfectly useful as checksums for detecting accidental changes or corruption, where nobody is deliberately attacking the hash. For everything else, choose SHA-256 or stronger.
How do I verify text or a file against an expected hash?
Enter your text or upload the file, select the same algorithm the expected hash uses (often SHA-256), and paste the expected value into the verify field. The tool computes the hash locally and reports whether it matches — a quick, exact way to confirm a download wasn't corrupted or tampered with. The comparison is case-insensitive, so uppercase or lowercase hex both work.
What output formats are supported?
Hex in lowercase, hex in uppercase, and Base64. Hex is the most common way to display a hash (the long string of 0-9a-f you see on download pages), while Base64 is more compact and sometimes used in headers or tokens. Pick whichever matches the value you're comparing against — a mismatch in format, not content, is a frequent reason two hashes look different.
Why do I get a different hash than another tool?
Almost always because the input differs, not the algorithm. Common causes: a trailing newline added by an editor, a different text encoding (UTF-8 vs UTF-16), different line endings (\n vs \r\n), or comparing a hex hash to a Base64 one. Hash the exact same bytes in the same format and the digests will match — the function is deterministic.
What is a hash actually used for?
Lots of things: verifying that a downloaded file arrived intact (checksums), detecting whether data has changed, deduplicating content by fingerprint, building cache keys and ETags, and — with the right construction — indexing or signing. Because the same input always yields the same fixed-length digest and any change alters it, a hash is a compact, reliable stand-in for "is this exactly the same data?".
Can it hash large files?
Usually yes, within your device's limits. Because hashing runs locally, the constraint is your browser's memory and CPU rather than a server cap. Small and medium files are near-instant; very large files take longer to read and process but are never uploaded. If you routinely hash big files, the dedicated File Hash Generator is optimized for that workflow.
Is it free, and are there limits?
Yes, completely free — no payment, no signup, no account, and no usage caps or watermarks. Since everything runs in your browser, there's nothing for us to meter; the only practical limit is your device's performance on very large inputs. Use it as much as you like, including offline once the page has loaded.
Still have questions?
If you can't find the answer you're looking for, feel free to contact our support team.