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SHA1 Encrypt

Generate a 40-character SHA1 hash from any text - type it in, click encrypt, and copy the result.

What is SHA1 Encrypt?

SHA-1 (Secure Hash Algorithm 1) condenses any input into a 160-bit digest, written as 40 hexadecimal characters. Like every hash function it is deterministic and one-way: the same text always gives the same hash, and no maths turns the hash back into the text. This tool runs Python's hashlib.sha1 and returns that 40-character string.

SHA-1 is no longer collision-resistant. NIST deprecated it in 2011, and in 2017 researchers produced a practical collision - the "SHAttered" attack - so it must not protect signatures, certificates or passwords. It still turns up across older systems, which is exactly where this tool is useful.

How to use the SHA1 tool

  • 1. Type or paste your text into the Your text field.
  • 2. Click Encrypt to generate the hash.
  • 3. The 40-character SHA-1 hash appears on the right - click Copy to grab it, or Reset to clear both fields.

Features

  • Standard 40-character hexadecimal SHA-1 output.
  • Deterministic - identical input always produces the same hash.
  • One-click Copy and Reset buttons.
  • Accepts any UTF-8 text.
  • Free to use with no sign-up.

When to use it

Matching a legacy SHA-1 checksum, reproducing a Git-style object fingerprint, or working with an older system that already expects SHA-1. For new integrity checks, or anything an attacker might want to forge, switch to SHA-256 instead - it is the modern default and just as easy to generate here.

FAQ

Is SHA-1 still safe to use?

No, not for security. NIST deprecated it in 2011 and a real collision (the SHAttered attack) was demonstrated in 2017. Use it only for legacy compatibility or non-security checksums, and pick SHA-256 for anything new.

How long is a SHA-1 hash?

160 bits, written as 40 hexadecimal characters, regardless of how long the input text is.

What is SHA-1 used for today?

Mostly legacy work: older Git object IDs, existing checksums and systems that already standardised on it. New projects should use SHA-256 or stronger.

Can a SHA-1 hash be reversed?

No, it is one-way. You can only confirm a guess by hashing it and comparing, which is why weak or short inputs are easy to brute-force.

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