Hash Generator

Generate MD5, SHA-1, SHA-256 and SHA-512 hashes for text or files — free, instant, and 100% in your browser.

Input

Text to hash

Uppercase output

Hashes update in real time as you type. Everything runs locally in your browser — nothing is sent to a server.

Hash Output

Hashes will appear here as you type.

About Hashing

A cryptographic hash function takes an input of any size and produces a fixed-length fingerprint. The same input always produces the same hash, but you cannot reverse a hash back to the original input. Hashes are used for integrity checks, password storage, digital signatures and content addressing.

MD5 (128-bit)

Fast and widely supported, but broken for security purposes. Collisions can be generated in seconds. Use only for non-adversarial checksums (e.g. deduplication).

SHA-1 (160-bit)

Also deprecated for security — practical collision attacks exist (SHAttered, 2017). Fine for legacy compatibility, not for new designs.

SHA-256 (256-bit)

Part of the SHA-2 family. No known practical attacks. The default choice for integrity checks, TLS, code signing and blockchain.

SHA-512 (512-bit)

Same family as SHA-256 but with a wider digest. Often faster than SHA-256 on 64-bit CPUs. Use when you want a larger security margin.

How to Use

Enter your text in the input box. You can type or paste any text, such as a password, an API string or a line of code.
See all hashes at once. MD5, SHA-1, SHA-256 and SHA-512 hashes update instantly as you type.
Choose upper or lower case. Tick “Uppercase output” if the system you are comparing against uses capital letters.
Copy the result. Click Copy next to the hash you need.
Start again. Click Clear to empty the input and the results.

Which Hash Should I Use?

Checking that data has not changed: use SHA-256. It is the standard choice for file downloads, software packages and APIs.
Working with an older system: use MD5 or SHA-1 only when an existing system requires them, such as legacy checksums or cache keys.
Extra security margin: use SHA-512 for signatures or long-term data integrity.
Storing passwords: do not use any of these on their own. Plain hashes are too fast and can be cracked with lookup tables. Use a password hashing algorithm such as bcrypt or Argon2, which add a salt and are deliberately slow.

How to Check a Downloaded File's Checksum

Many websites publish a SHA-256 checksum next to their downloads so you can confirm the file was not damaged or changed. This tool hashes text, so to check a file, run one of these commands in a terminal and compare the result with the published checksum:

Linux: sha256sum filename
macOS: shasum -a 256 filename
Windows (PowerShell): Get-FileHash filename -Algorithm SHA256

If even one character is different, the file is not the same as the original. Download it again from the official source.

Frequently Asked Questions

What is a hash?

A hash is a one-way fingerprint of data. Given the same input, a hash function always returns the same fixed-length output. Given only the hash, you cannot recover the input.

What's the difference between MD5 and SHA-256?

MD5 produces a 128-bit digest and is cryptographically broken, because collisions are easy to create. SHA-256 produces a 256-bit digest and has no known practical attacks. For anything security-related, use SHA-256 or SHA-512.

Is this tool safe to use with sensitive text?

Yes. All hashing happens locally in your browser. Your text never leaves your device and nothing is uploaded to any server.

Can a hash be reversed or decrypted?

No. Hashing is not encryption, so there is no key to reverse it. However, short or common inputs such as simple passwords can be guessed by comparing them against huge lists of precomputed hashes, which is why weak passwords are unsafe even when hashed.

Why does a small change give a completely different hash?

Good hash functions are designed so that changing a single character, even a space or a capital letter, produces a completely different result. This makes hashes reliable for detecting any change in data.

Do upper-case and lower-case hashes mean the same thing?

Yes. A hash is a hexadecimal number, so ABC123 and abc123 represent the same value. Use whichever case the system you are comparing against expects.

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