SHA256 OnlineDebug a request signature
Decode the same message and key bytes used by the other implementation before comparing HMAC-SHA256.
SHA-2 · 256 bits · Text
SHA256 Hash Generator
Calculate SHA256 from UTF-8, Hex or Base64 text. Compare a trusted expected digest locally.
Input No upload
Output Your result · SHA256
SHA256 calculated
0 decoded bytes · UTF-8 · input changes update automatically
Browser-local hashing. Inputs masked in Clarity.
No account. No uploads. Just your browser.
Generate SHA256 from exact bytes
- 1
Enter or decode your message
Start empty, paste UTF-8 text, or choose Hex or Base64 for encoded bytes.
- 2
Inspect the full digest
SHA256 returns 64 lowercase hex characters. Copy digest preserves the whole output.
- 3
Compare or reproduce a keyed result
Paste a trusted reference, or enable HMAC only for a keyed protocol.
SHA256 text workflows
Check a software release
Use the publisher’s SHA256 for the exact version, platform and archive.
Inspect newline differences
Try a literal message and then the same message with Enter to see why byte-exact fixtures matter.
SHA256 versus SHA512
| Algorithm | What differs |
|---|---|
| SHA256 | 256-bit digest: 64 hexadecimal characters. |
| SHA512 | 512-bit digest: 128 hexadecimal characters; not a padded SHA256. |
Details that affect your SHA256 result
How SHA256 works
SHA256 is part of SHA-2 and produces a 256-bit result: 64 hexadecimal characters. It is a common choice for verifying downloads against a trusted publisher’s checksum. Hashing is one-way, not encryption.
If a SHA256 checksum differs, first confirm the download version and platform. A checksum for a Linux archive will not match the Windows installer, even if both carry the same release number.
Generate a SHA256 hash from exact bytes
Type or paste text for an automatic result. UTF-8 preserves whitespace and line endings. Hex accepts pairs of digits with optional whitespace; Base64 requires the standard padded alphabet. Invalid encoding stops calculation instead of hashing a different input.
The default result is the digest of zero bytes. The abc example contains exactly 61 62 63 in hex with no newline. Adding Enter changes the bytes and therefore the result.
Compare a value or use a key
Paste a complete hexadecimal expected value to see Match or Mismatch. Outer whitespace and uppercase hex are accepted; incomplete digests, filenames and embedded spaces are not.
HMAC-SHA256 calculates a keyed hash. Enable HMAC and enter the secret in its own encoding. An empty key is a valid key and differs from turning HMAC off. Keys are never saved or included in exported reports.
Switch to files without changing the algorithm
The SHA256 file checksum tool reads raw bytes in chunks and supports batch manifests. Text mode is limited to 8 MiB decoded input; use file mode for larger data.
No input is uploaded. Only a light/dark theme preference is stored. Copy and report downloads remain on your device.
Known SHA256 result: empty input
SHA256 · 0 bytes · no HMAC. Empty input is not the same as no file selected.
e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855SHA256 hash generator FAQ
How is this generator different from the home page?
This focused SHA256 hash generator starts with empty text. The SHA256 online home page starts with an explicit abc example and introduces text and file verification.
Is SHA256 part of SHA-2 or SHA-3?
SHA256 is a SHA-2 algorithm. SHA3-256 is a different design; the two produce 256-bit results but do not produce the same digests.
Should I paste 616263 as UTF-8 or Hex?
For the bytes of abc choose Hex and enter 616263. UTF-8 hashes the six visible characters 616263 instead, so it produces a different SHA256.
Why does an empty HMAC key change SHA256?
Enabling HMAC selects a different construction even if the key has zero bytes. Disable HMAC when comparing an ordinary SHA256 digest.
How do I hash encoded bytes with SHA256?
UTF-8 hashes literal text. Hex and standard padded Base64 decode to bytes first. abc, Hex 616263 and Base64 YWJj represent the same bytes; invalid encodings stop calculation.
Will spaces or Enter change my SHA256?
Yes. Text is not trimmed. A trailing newline, carriage return, byte-order mark or extra space changes the byte sequence and usually the result.
How do I compare a SHA256 expected value?
Paste exactly 64 hexadecimal characters. Uppercase and outer whitespace are accepted. Match means equality with your reference, not proof of a trustworthy source.
Where does this SHA256 generator store my input?
Text and keys stay in browser memory, not URLs or localStorage. The tool saves only your theme preference; Clarity may use its own identifiers, as explained in Privacy. Text mode accepts up to 8 MiB of decoded bytes; use file mode for larger inputs.