SHA-1 Hash Generator - Free Online Tool | ToolVault
100% LocalFree online SHA-1 hash generator: paste text and instantly get the 40-character hex digest. Covers git commit IDs and legacy checksums. Computed locally in your browser, never uploaded.
TL;DR: Free online SHA-1 hash generator producing the 40-character hex digest. Covers git IDs and legacy checksums. Computed locally via Web Crypto API, never uploaded.
This tool runs entirely in your browser. Open DevTools → Network panel and search your input — it appears in no request.
Next steps
使用指南
SHA-1 compresses any input into a 160-bit (40 hex characters) fingerprint. It was practically broken by Google’s SHAttered collision in 2017 and is retired from security use — but git commit IDs, early payment/open-platform signatures, and legacy checksum fields are still SHA-1 everywhere. This page computes locally with the browser’s Web Crypto API; your text never crosses the network.
1. Get a SHA-1 in three steps
Empty input yields the SHA-1 of the empty string (the fixed value starting da39) rather than an error — that is correct hash behavior. If the output is a fixed-looking value, check the paste was complete.
- Paste your text into the input box (a config snippet, an API payload, historical data to compare).
- Confirm the algorithm dropdown stays on SHA-1 — this page defaults to it.
- Click Compute, then copy the 40-character hex digest from the output box.
2. Where SHA-1 still lives
The most prominent survivor is git: every commit ID is SHA-1 (the project is migrating to SHA-256, but existing repositories are all SHA-1). You will also meet it in early open-platform API signatures and checksum columns in legacy databases. For those cases you just need the right answer — this page exists for compatibility, not to endorse new adoption.
3. One security red line to remember
- SHA-1 collisions are practical: Google’s 2017 SHAttered demo produced two different PDFs with the same SHA-1. Never use SHA-1 for signatures, certificates, password storage, or any anti-forgery purpose — switch to SHA-256 or SHA-512 in this page’s dropdown.
- Verifying legacy data against SHA-1 carries no shame — checksumming historical data is a compatibility operation, not a security decision.
4. SHA-1 vs MD5 vs SHA-256
MD5 is 128-bit (32 chars), fastest and easiest to collide; SHA-1 is 160-bit (40 chars) and also broken; SHA-256 is 256-bit (64 chars) and the current industry default. The rule is simple: integrate with legacy systems using whatever they use; design new systems starting from SHA-256.
FAQ
Completely free, no registration. Paste text to compute the SHA-1 hash instantly — all computation happens locally in your browser with no usage limits.
No. Google’s 2017 SHAttered attack demonstrated a practical SHA-1 collision. Do not use SHA-1 for signatures, certificates, or password storage — use SHA-256 or SHA-512. This page exists mainly for legacy compatibility such as git commit IDs and old API signatures.
SHA-1 outputs 160 bits, which is 40 hexadecimal characters. MD5 is 32 chars and SHA-256 is 64 — you can tell the algorithms apart by length alone.
Never. All computation uses the browser’s native Web Crypto API locally. Your text never leaves your device, so sensitive configs and internal data are safe.
Both are broken hash algorithms. MD5 is 128-bit, faster, and easier to collide; SHA-1 is 160-bit with a higher but practical collision cost. Use whatever a legacy system requires; start new systems from SHA-256.
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