Encrypt/Decrypt
Online encryption/decryption tool
Overview
Our online encryption and decryption tool supports mainstream symmetric encryption algorithms including AES, DES, and 3DES, with ECB, CBC, CTR, and GCM modes. All operations are performed locally in your browser without uploading data to any server, keeping your sensitive information secure. Ideal for API debugging, secure data transmission, and learning cryptography.
Features
- AES-128/192/256 encryption and decryption
- DES encryption and decryption
- 3DES encryption and decryption
- ECB/CBC/CTR/GCM modes
- Custom key and IV support
- Base64 and Hex encoded output
- Automatic PKCS7 padding handling
How It Works
- Enter the plaintext or ciphertext in the input field
- Select the algorithm and mode, then configure the key and IV
- The tool uses the Web Crypto API to perform encryption or decryption in the browser
- Get the result in Base64 or Hex format
Tips
- Prefer AES-256-GCM for the best balance of security and performance
- Generate keys and IVs with a cryptographically secure random number generator, never use simple passwords directly
- Encryption and decryption must use identical algorithm, mode, key, and IV, or decryption will fail
FAQ
What is the difference between AES and DES?
AES (Advanced Encryption Standard) uses 128/192/256-bit keys, offering higher security and better performance. It is the most widely used symmetric encryption algorithm today. DES uses a 56-bit key and is no longer considered secure, used only for legacy compatibility. 3DES is an improved version of DES that applies triple encryption but is slower than AES.
What is the difference between ECB and CBC modes?
ECB mode encrypts each block independently, so identical plaintext blocks produce identical ciphertext blocks, leaking data patterns. CBC mode introduces an initialization vector (IV), making each ciphertext block dependent on the previous one for better security. CBC or GCM modes are recommended.
How should I set the key and IV?
AES-256 requires a 32-byte key, AES-128 requires a 16-byte key. The IV should typically be the same length as the key and must be randomly generated and never reused. CBC mode requires an IV, while ECB mode does not.