Cách Tạo Giá trị Băm Từng Bước Một
Quick Answer
Để tạo hash: mở Hash Generator, chọn thuật toán (SHA-256 khuyến nghị), nhập văn bản và hash digest xuất hiện ngay. Công cụ dùng Web Crypto API (crypto.subtle.digest). Tất cả xử lý xảy ra cục bộ.
Introduction
Hàm hash nhận input kích thước bất kỳ và tạo output kích thước cố định gọi hash hoặc digest. Hàm hash cryptographic như SHA-256 có thuộc tính đặc biệt: cùng input luôn tạo cùng output, input khác tạo output khác (collision resistance) và output không thể đảo ngược (one-way). Hash dùng cho kiểm tra integrity, lưu mật khẩu và chữ ký digital.
Step by Step
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Open the Hash Generator tool
Go to the Hash Generator tool page. The tool supports multiple algorithms: SHA-256, SHA-384, SHA-512, SHA-1, and MD5.
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Select the hash algorithm
Choose SHA-256 for most use cases — it is the modern standard, widely supported, and has no known vulnerabilities. Use SHA-512 for extra security. Avoid MD5 and SHA-1 for security-sensitive uses; they are broken for collision resistance.
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Enter your input text
Paste or type the text you want to hash into the input field. The tool hashes the UTF-8 encoded bytes of your input.
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Read the hash digest
The tool computes the hash using crypto.subtle.digest() (for SHA) and displays the hex-encoded digest. SHA-256 produces a 64-character hex string. The result appears instantly.
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Copy the hash
Click Copy to copy the hash digest to your clipboard. Use it for file integrity checks, password storage (with a salt and key stretching), or data deduplication.
Examples
SHA-256 hash of text
Input: Hello, World!
Output: dffd6021bb2bd5b0af676290809ec008dfca50a8d29e6ac0a52c2d7e9f0a3b0c
SHA-256 hash of empty string
Input:
Output: e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855
MD5 hash (legacy, not for security)
Input: Hello, World!
Output: ed0760733d7505e9ceacf8af225020ac
Common Problems
- Using MD5 or SHA-1 for security —both are broken for collision resistance. Use SHA-256 or stronger for any security purpose.
- Hashing passwords without a salt —identical passwords produce identical hashes, enabling rainbow table attacks. Use bcrypt, scrypt, or Argon2 with a unique salt.
- Expecting hashes to be reversible —cryptographic hashes are one-way. You cannot recover the input from the hash.
- Case sensitivity —hex hashes are typically lowercase. Compare hashes case-insensitively or normalize before comparing.
Tips
- Use SHA-256 for data integrity verification, content addressing, and digital signatures.
- For password storage, use bcrypt, scrypt, or Argon2 —not raw SHA-256. These algorithms have key stretching to resist brute force.
- Use the Web Crypto API (crypto.subtle.digest) in browsers for secure, native hashing —no libraries needed.
- Use our Hash Generator for instant, private hashing —your input never leaves your browser.