Example and common questions

Generate checksums for text, files, or entire folders with 48 algorithms, including SHA-256, SHA-3, MD5, BLAKE3, xxHash, and CRCs. Select file types and folders, process batches, and export local reports to compare exact bytes. UTF-8 text includes spaces and line endings; Files mode preserves raw binary bytes.

How to calculate a hash or checksum

Under Choose what to checksum, select Text for pasted input or Files. In Files mode, use Choose files or Choose folder, or drop files and folders into the marked area. Subfolders are included. Use Choose files to process to include or exclude file types, folders, or individual files. Set Concurrent workers with the 1–16 slider (default 4).
Select an algorithm family and variant. For SHAKE or BLAKE3, choose the digest length in bytes.
Choose lowercase hex, uppercase hex, or Base64 output, then calculate. Copy a text digest or copy file paths and checksums as plain text. Download text checksums or a JSON/CSV report, or use Send Markdown to notebook or Send JSON to notebook to create a note.

SHA-256 of abc without a newline

Algorithm: SHA 256
Text or bytes: utf8
Digest output: hex lower
Digest bytes: 32

Input

abc

Checksum

ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad

Does it hash the exact text?

Yes. UTF-8 mode includes whitespace and line endings. Hex mode hashes the specified bytes and ignores whitespace between hex digits.

Can I hash multiple files, including binary files?

Yes. Choose Files, then Choose files or Choose folder. All accessible files, including nested files, are processed in batches of 100 using the selected algorithm. Choose 1–16 concurrent workers with the slider; it starts at 4. Include or exclude files by type or folder before generating. Only included files are processed, copied, or exported. Files are read in chunks without text conversion or uploads. Cancel keeps completed results; retry processes unfinished files. File selections stay in this tab and are cleared when you leave, switch to Text, or reload. Download results or send them to the notebook as Markdown or JSON first. A saved note contains the included file results; use its Open note link to view it.

Is my input uploaded?

No. Calculation runs in a browser worker using locally bundled hashing libraries. The input draft is saved locally until you clear it.

All 48 supported hash and checksum algorithms

Generate 48 hash and checksum variants from UTF-8 text, hexadecimal bytes, files, or folders.
Include subfolders, select files by type or folder, and process selections in batches of 100.
Choose 1–16 concurrent workers (default 4), cancel processing, and retry unfinished files.
Copy file paths and checksums as plain text, or download text, JSON, and CSV reports.
Output lowercase or uppercase hexadecimal or Base64; SHAKE and BLAKE3 support 1–1,024 digest bytes.
Send included results directly to a new Markdown table or JSON note in the notebook.
Read raw file bytes locally in 1 MiB chunks without uploads.

SHA-2: SHA-224, SHA-256, SHA-384, SHA-512, SHA-512/224, SHA-512/256
SHA-3: SHA3-224, SHA3-256, SHA3-384, SHA3-512
Keccak: Keccak-224, Keccak-256, Keccak-384, Keccak-512
Variable-length hashes: SHAKE128, SHAKE256, BLAKE3
BLAKE2: BLAKE2b-128, BLAKE2b-160, BLAKE2b-224, BLAKE2b-256, BLAKE2b-384, BLAKE2b-512, BLAKE2s-128, BLAKE2s-160, BLAKE2s-224, BLAKE2s-256
Other hashes: SM3, Whirlpool
Legacy hashes: MD4, MD5, SHA-1, RIPEMD-160
Fast non-cryptographic hashes: xxHash32, xxHash64, xxHash3-64, xxHash3-128
Checksums and CRCs: Adler-32, CRC-8/SMBUS, CRC-16/ARC, CRC-16/MODBUS, CRC-16/CCITT-FALSE, CRC-16/XMODEM, CRC-16/KERMIT, CRC-32, CRC-32C, CRC-64/XZ, CRC-64/ECMA-182

Common errors and limitations

Hex input requires complete byte pairs. Text input is limited to 1,000,000 UTF-16 characters. Files use 1 MiB chunks without that text limit. Selections can exceed 100 files: batches of 100 run in sequence with 1–16 concurrent file workers chosen by slider (default 4). File-type groups use case-insensitive filename extensions; dotfiles such as .env and extensionless files appear under No extension. Folder groups include their subfolders. Changing one group updates overlapping group counts and partially checked states. New files start included. Results show 20 files per page. Empty folders have no checksum. Folder selection requires browser support. A stalled read stops after 60 seconds without progress. CSV reports prefix formula-like cells for spreadsheet safety; JSON retains verbatim filenames, relative paths, and checksums. Copy includes completed checksums and paths as plain text, limited to 2,000,000 characters; use the text download for larger manifests. These checksums are not password hashing or encryption. SHAKE and BLAKE3 output is limited to 1,024 bytes. MD4, MD5, SHA-1 and RIPEMD-160 are legacy compatibility choices; CRC, Adler and xxHash are non-cryptographic. Keccak differs from SHA-3. xxHash uses seed zero; BLAKE hashes are unkeyed. CRC-32 means ISO-HDLC; CRC-32C means Castagnoli; the CRC-64 variants name their exact parameters. No finite list includes every checksum ever devised.