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Hash Generator

Hash text or a file with MD5, SHA-1, SHA-256, SHA-512, SHA-3, BLAKE2, BLAKE3, CRC32 and more, all computed live as you type. Compare against an expected checksum and copy any digest.

Everything runs locally in your browser. Your data never leaves your device.

Input

0 characters

Options

Turns the cryptographic and legacy hashes into keyed HMACs. The key is not saved.

Algorithms

Pick which digests to compute. All selected algorithms run in one pass.

CryptographicCollision-resistant, safe for integrity and signatures.
Checksums and fast hashesNot cryptographic. Good for error detection and hashing speed, not security.
LegacyBroken for security use. Only for compatibility with old systems.

Verify a checksum

Casing, whitespace, colons and a pasted checksum-file line are all fine. A matching digest below lights up green.

Digests

Digests appear as you type.

0 of 7 digests computed
CryptographicCollision-resistant, safe for integrity and signatures.
SHA-256
–
SHA-512
–
SHA3-256
–
BLAKE3
–
Checksums and fast hashesNot cryptographic. Good for error detection and hashing speed, not security.
CRC-32
–
LegacyBroken for security use. Only for compatibility with old systems.
MD5not collision-resistant
–
SHA-1not collision-resistant
–

Next steps

Send this tool's output straight into another tool.

Text Case Converter

Convert text into every case at once: title case in the APA, AP, Chicago, MLA, Bluebook, AMA and NYT styles, sentence case, upper, lower, camelCase, snake_case, kebab-case and more.

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Word & Character Counter

Count words, characters, sentences, paragraphs, lines and more as you type, with estimated reading and speaking time.

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Dedupe Lines

Remove duplicate lines from a list or text, keeping the first occurrence. Optionally ignore case and whitespace, or drop blank lines too.

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Find and Replace

Replace text in two modes: plain find and replace all, or regular expressions with flag controls and capture group references like $1.

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Text Diff

Compare two texts and see every added, removed and changed line highlighted, side by side or inline, with the changed words marked within each line. Ignore case, whitespace or blank lines, read a summary of how much changed, and export the result as a unified diff.

textdev

UUID Decoder

Paste a UUID to see what it carries: version, variant, and for time-based versions the exact timestamp, clock sequence and node. Also shows the raw bytes, the 128-bit integer and the URN form.

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Base64 Encoder & Decoder

Decode Base64 to text or encode text to Base64. Paste into the top box, read the result below, and flip the direction with one click. Handles Unicode correctly, reads URL-safe Base64, and shows binary payloads as a hex dump you can download.

devconvertertext

Number Base Converter

Convert numbers between binary, octal, decimal, hexadecimal and any base up to 36. Type into any field and the others update as you go. Handles huge integers without losing precision and accepts 0x, 0b and 0o prefixes.

devconvertercalculator

Scientific Notation Converter

Convert between scientific notation and full numbers as you type. Reads 1.23e5, 1.23 × 10^5 and plain numbers, shows the value written out, in normalized scientific notation and in engineering notation, and can round to any number of significant digits.

convertercalculator

About the Hash Generator Tool

This tool computes checksums and cryptographic hashes of text or a file with more than twenty algorithms, from MD5, SHA-1 and SHA-256 to SHA-3, Keccak-256, BLAKE2, BLAKE3, RIPEMD-160, CRC-32 and the xxHash family. Text is hashed live as you type, and files are read in chunks, so even multi-gigabyte downloads hash without trouble.

Pick the algorithms you care about, switch the digest format between lowercase hex, uppercase hex and Base64, and copy any digest with one click. Paste an expected checksum to verify a download, the matching digest lights up green. An optional secret key turns the cryptographic algorithms into HMACs.

What you can do

  • Generate an MD5, SHA-1, SHA-256 or SHA-512 hash of any text.
  • Verify a downloaded file against a published SHA-256 or MD5 checksum.
  • Compute SHA-3, Keccak-256, BLAKE2, BLAKE3, RIPEMD-160, CRC-32 and xxHash digests.
  • Calculate an HMAC-SHA256 signature with a secret key.
  • Copy a digest as lowercase hex, uppercase hex or Base64.

How to use the Hash Generator

  1. 1Choose Text or File as the input, then type your text or drop the file in.
  2. 2Tick the algorithms you want. Every selected algorithm is computed in one pass.
  3. 3Pick hex or Base64 as the digest format, and enter an HMAC key if you need a keyed hash.
  4. 4To verify a checksum, paste the expected digest. The matching row turns green.
  5. 5Copy a single digest with its copy button, or copy the whole list at once.

Which algorithm should you use?

For anything security-related, use SHA-256 or stronger. SHA-3 is the current NIST standard, and BLAKE2 and BLAKE3 are modern, very fast alternatives. MD5 and SHA-1 are broken for collision resistance, so treat them as legacy fingerprints for compatibility with old systems, never as protection against tampering.

CRC-32, Adler-32 and the xxHash family are not cryptographic at all. They are built to catch accidental corruption and to be fast, which makes them a good fit for integrity checks, cache keys and deduplication, and a bad fit for anything an attacker could touch. The tool groups them separately so the difference stays visible.

Verifying a downloaded file

Download pages often publish a SHA-256 or MD5 checksum next to the file. Switch the input to File, drop the download in, and paste the published digest into the verify field. The comparison ignores casing, whitespace and colon separators, and it understands a full sha256sum output line, so you can paste the line with the filename still attached.

When a row lights up green, the file on your disk is byte-for-byte the file the publisher hashed. If nothing matches, the download is corrupted, incomplete or not the file you expected.

Keyed hashes (HMAC)

Enter a key to compute HMACs instead of plain hashes. An HMAC proves a message came from someone who knows the key, which is how webhook payloads and API requests are commonly signed. HMAC works with the cryptographic and legacy algorithms, checksums like CRC-32 have no HMAC form. The key is kept in memory only and is not written to storage.

Credits

Open source does the heavy lifting in this tool. Thank you to:

  • hash-wasm

    Hand-tuned WebAssembly implementations of MD5, SHA, BLAKE, bcrypt, Argon2 and many more.

Everything this site builds on is listed on the credits page.

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