DES Encrypt / Decrypt
Encrypt and decrypt data with the DES algorithm in CBC, CFB, CTR, OFB, and ECB modes
What is DES encryption?
DES (Data Encryption Standard) is a historic symmetric block cipher that was the U.S. federal encryption standard from 1977 to 2001. It encrypts data in 64-bit blocks using a 56-bit key, but its small key size makes it vulnerable to brute-force attacks — a DES key can be cracked in hours with modern hardware.
DES is provided here for legacy system compatibility and educational purposes only. For any new application, use AES-256 instead. This tool supports all five DES modes of operation: CBC, CFB, CTR, OFB, and ECB.
How to use DES Encrypt / Decrypt
Enter your data and key
Type or paste the text to encrypt or decrypt and enter your 8-character (56-bit effective) DES key.
Configure mode
Select a mode of operation (CBC is most common for legacy systems) and provide an IV if required.
Click Encrypt or Decrypt
The output appears instantly in your browser.
Copy the result
Click Copy to use the output in your application.
Frequently asked questions
Why is DES considered insecure?
DES uses a 56-bit key, which provides only 2^56 possible keys. Modern hardware can try all possible keys in a matter of hours, making DES vulnerable to brute-force attacks. It was officially retired by NIST in 2005.
What is the difference between DES and Triple DES?
Triple DES (3DES) applies DES three times with two or three independent keys, achieving 112-bit or 168-bit effective key strength. It is slower than AES but was used as an interim upgrade from single DES before AES was widely adopted.
When would I use DES?
Only when interoperating with legacy systems that were built before AES adoption and cannot be updated. No new system should use DES for security.
Is my data sent to a server?
No. All DES operations run in your browser. Your data and keys are never transmitted.