SHA-1 Hash Generator
Computed in your browser — your text is never sent to a server.
What is SHA-1 Hash Generator
SHA-1 (Secure Hash Algorithm 1) is a cryptographic hash function developed by the NSA and published in 1995. It converts any input into a fixed 40-character hexadecimal string (160 bits). Although SHA-1 is no longer considered secure for digital signatures and certificates — deprecated by major browsers and certificate authorities — it remains in use in legacy systems, version control (Git uses SHA-1 for object IDs), and HMAC authentication. This tool computes SHA-1 hashes entirely in your browser using the native Web Crypto API.
How to use
- Type or paste any text into the input field.
- The SHA-1 hash updates instantly as you type.
- Click Copy to copy the 40-character hash to your clipboard.
- To switch to another algorithm, choose MD5, SHA-256, or SHA-512 from the Algorithm dropdown — your input is preserved.
When to use it
Maintaining a legacy auth system and need to confirm a token is legitimate? Paste the value your client sent, get its SHA-1, and compare it against the stored HMAC-SHA1 digest to see if the request checks out. It also works for spotting whether two strings are byte-for-byte identical or verifying a Git object ID by hand.
Frequently asked questions
Is SHA-1 still secure?
SHA-1 is no longer considered secure for cryptographic purposes. Collision attacks against SHA-1 have been publicly demonstrated. For new applications, use SHA-256 or SHA-512.
How long is a SHA-1 hash?
SHA-1 produces a 160-bit value displayed as 40 hexadecimal characters, regardless of the input size.
Why does Git use SHA-1?
Git adopted SHA-1 for object IDs in the 1990s when it was still considered secure. Git is transitioning to SHA-256 in newer versions, but SHA-1 remains the default for compatibility.
Is my text sent to a server?
No. SHA-1 is computed in your browser using the Web Crypto API. Your input never leaves your device.
Can I share this tool with my inputs pre-filled?
Yes. The URL updates automatically as you type. Copy it from the address bar or use the Share button — anyone who opens the link will see your exact inputs ready to go.
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