What Is the SHA-1 Hash of "The quick brown fox jumps over the lazy dog"?
The SHA-1 hash of "The quick brown fox jumps over the lazy dog" is 2fd4e1c67a2d28fced849ee1bb76e7391b93eb12. This is a 40-character hexadecimal string representing 160 bits. Even a single-character change to the input produces a completely different hash due to the avalanche effect.
About SHA-1
SHA-1 (Secure Hash Algorithm 1) produces a 160-bit (40-character hex) hash. Developed by the NSA and published by NIST in 1995, SHA-1 was the standard for TLS certificates, Git commits, and file integrity. In 2017, Google demonstrated the first practical SHA-1 collision (SHAttered). SHA-1 is deprecated for security uses -- modern applications should use SHA-256 or SHA-3.
How SHA-1 Computes This Hash
- Pad the message to a multiple of 512 bits (append 1 bit, zeros, then 64-bit length)
- Initialize five 32-bit state variables (h0-h4) to fixed constants
- Expand each 512-bit block into 80 32-bit words using XOR and left rotation
- Process through 80 rounds using nonlinear functions (Ch, Parity, Maj)
- After all blocks, concatenate h0-h4 to produce the 160-bit digest
Hash Details
| Input | The quick brown fox jumps over the lazy dog |
| Algorithm | SHA-1 |
| Hash (hex) | 2fd4e1c67a2d28fced849ee1bb76e7391b93eb12 |
| Character count | 40 hex characters |
| Bit length | 160 bits |
Security warning: SHA-1 is cryptographically broken. Do not use it for passwords, digital signatures, or any security-critical purpose. Use bcrypt, Argon2, or scrypt for password hashing, and SHA-256+ for data integrity.
Verify It Yourself
JavaScript (Node.js)
require('crypto').createHash('sha1').update('The quick brown fox jumps over the lazy dog').digest('hex');
// "2fd4e1c67a2d28fced849ee1bb76e7391b93eb12"Python
import hashlib
hashlib.sha1(b'The quick brown fox jumps over the lazy dog').hexdigest()
# '2fd4e1c67a2d28fced849ee1bb76e7391b93eb12'Bash
echo -n 'The quick brown fox jumps over the lazy dog' | sha1sum
# 2fd4e1c67a2d28fced849ee1bb76e7391b93eb12 -Try It Yourself
Use our SHA-1 Hash Generator to hash any string instantly.
Frequently Asked Questions
Is SHA-1 safe to use in 2026?
SHA-1 is cryptographically broken and should not be used for security purposes. It is still acceptable for non-security checksums and cache keys.
Can I reverse a SHA-1 hash?
No. SHA-1 is a one-way function. Common inputs like "The quick brown fox jumps over the lazy dog" can be found via rainbow tables, which is why you should never use plain SHA-1 for passwords -- use bcrypt or Argon2 instead.
What is the avalanche effect?
The avalanche effect means that a tiny change in the input (even one bit) causes roughly 50% of the output bits to change. This makes it impossible to predict the hash of a similar input from a known hash.