SHA-3 · 256 bits · Files
Calculate SHA3-256 for one or many files. Verify a GNU or BSD checksum list without uploading files.
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Browser-local hashing. Inputs masked in Clarity.
No account. No uploads. Just your browser.
Choose up to 100 files, each at most 2 GiB. The file contents are read locally.
SHA3-256 returns 64 lowercase hex characters. Copy digest preserves the whole output.
Read a local manifest or paste a trusted expected value. Review each filename and any missing entries.
SHA3-256 uses the SHA-3 standard and produces 64 hexadecimal characters. It is not SHA256 and is not Keccak-256: their padding rules differ, so identical input produces different digests.
Select SHA3-256 explicitly when your source names it. A blockchain Keccak-256 checksum must not be tested with SHA3-256. Equal output lengths do not identify an algorithm.
Choose or drop files and calculation starts automatically. Each file is read sequentially in 2 MiB chunks inside a background worker. Up to 100 files and 2 GiB per file are accepted. Cancel terminates the active worker.
Paste a trusted expected digest to compare directly. With no expected value, Not compared yet is not a verification success. Every batch row includes the complete digest, byte count and comparison outcome.
Open manifest options to read a local list or paste GNU digest–filename lines or BSD ALGORITHM (filename) = digest lines. Verify selected files runs the comparison again with the list. The filename is matched exactly, including spaces and relative folders.
Duplicate names, invalid digest lengths, mixed algorithms and unsupported lines block manifest verification. Missing files and files not listed are displayed; no basename-only guessing or silent success is used. Lists are limited to 1 MiB and 100 entries.
Hashing runs in browser memory with no upload endpoint. Microsoft Clarity runs on this page, with the entire tool workspace masked, including filenames, digests and manifests. Google Analytics runs only on the four information pages. A local report can be copied or downloaded. See Privacy for details.
The 2 GiB ceiling is not a promise about every phone. If a device struggles, cancel and use a system checksum utility. A matching value proves only equality with the reference digest, not safety or publisher identity.
Select SHA3-256 only when the trusted list names that exact algorithm, not merely a 64-character digest.
Keccak-256 and standardized SHA3-256 differ. A Keccak reference cannot verify this result.
Raw file bytes are hashed directly. Text encodings and newline conversion are not applied in file mode.
| Algorithm | What differs |
|---|---|
| SHA3-256 | SHA-3 construction standardized in FIPS 202. |
| SHA256 | SHA-2 construction standardized in FIPS 180-4; a different digest. |
SHA3-256 · 0 bytes · no HMAC. Empty input is not the same as no file selected.
SHA256 Onlinea7ffc6f8bf1ed76651c14756a061d662f580ff4de43b49fa82d80a4b80f8434aDigest length is the same but the algorithms differ. Rehash the original file with SHA3-256 rather than copying a SHA256 value into this page.
Not in general. Keccak-256 is not the SHA3-256 algorithm used by this tool. Obtain a reference explicitly labeled SHA3-256.
The parser accepts the SHA3-256 algorithm name (with the hyphen) for this route. A list labeled SHA256 or SHA512 is a different algorithm and must not be relabeled.
No. This page has a fixed 256-bit SHA3 digest. Variable-length SHAKE output needs the matching SHAKE function and output-length setting in another tool.
Files are hashed automatically and sequentially. The result says calculated until an expected digest is supplied; Match or Mismatch describes a comparison, not just a completed calculation.
Use GNU digest followed by a filename, or a BSD algorithm (filename) = digest line. Each SHA3-256 reference needs 64 hex characters. Malformed lines and duplicate names block verification.
Names must match exactly, including spaces and relative paths. A selected file not in the manifest is reported separately and is not silently treated as a verified match.
Download report saves a local text report with filenames, byte counts, digests and comparison states. Keep that report private if its filenames or checksums are sensitive. No report is uploaded.