A consolidated reference for the symmetric ciphers exposed by Utilavo's encryption tools. Status, key and block sizes, and deprecation dates are sourced directly from NIST SP 800-131A Rev 2 and SP 800-57 Part 1 Rev 5 so the recommendation column is auditable.
Key findings
- AES is the only cipher in this dataset that NIST approves for new systems, at all three key sizes: 128, 192, and 256 bits (FIPS 197).
- Triple DES is disallowed in both forms: the 2-key variant since 2015 (SP 800-131A Rev 1) and the 3-key variant for new encryption after 2023 (SP 800-131A Rev 2).
- DES stopped being a federal standard when FIPS 46-3 was withdrawn in 2005.
- RC4 was never approved by NIST, and RFC 7465 prohibited it in TLS in 2015.
- Every cipher in this dataset without NIST approval uses a 64-bit block or is a stream cipher; the approved options all share AES's 128-bit block.
Methodology
Each algorithm row is populated from its current entry in NIST's transition guidance documents. The recommended column reflects the 2026 NIST guidance for new systems; deprecated_year reflects the year the algorithm was first formally disallowed for the relevant federal use case. No measurements are taken: this is a reference matrix, not a benchmark.
See the site-wide research methodology for shared test conditions and tooling.
Dataset
| Algorithm | Key size (bits) | Block size (bits) | NIST status | Deprecated (year) | Recommended for new systems |
|---|---|---|---|---|---|
| AES-128 | 128 | 128 | Approved (FIPS 197) | N/A | Yes |
| AES-192 | 192 | 128 | Approved (FIPS 197) | N/A | Yes |
| AES-256 | 256 | 128 | Approved (FIPS 197) | N/A | Yes (recommended for long-term confidentiality per SP 800-131A Rev 2) |
| Triple-DES (3-key TDEA) | 168 | 64 | Disallowed for federal use after 2023 (SP 800-131A Rev 2) | 2023 | No |
| Triple-DES (2-key TDEA) | 112 | 64 | Disallowed since 2015 (SP 800-131A Rev 1) | 2015 | No |
| DES | 56 | 64 | Withdrawn: FIPS 46-3 withdrawn in 2005 | 2005 | No |
| RC4 | 40-2048 | N/A (stream) | Never approved by NIST; prohibited in TLS by RFC 7465 (2015) | 2015 | No |
Download raw data
The raw CSV contains every row in the table above plus any columns omitted from the rendered view.
Download CSVCitations
Related tools
- Encrypt / DecryptEncrypt and decrypt data with AES, DES, Triple DES, and RC4 symmetric ciphers
- AES Encrypt / DecryptEncrypt and decrypt data with AES-128, AES-192, or AES-256 in CBC, CFB, CTR, OFB, and ECB modes
- DES Encrypt / DecryptEncrypt and decrypt data with the DES algorithm in CBC, CFB, CTR, OFB, and ECB modes
- Triple DES Encrypt / DecryptEncrypt and decrypt data with Triple DES (3DES) using double or triple key lengths
- RC4 Encrypt / DecryptEncrypt and decrypt data with the RC4 stream cipher with configurable key size and drop bytes
- Protect PDFPassword-protect and encrypt a PDF document
Related guides
AES vs DES vs Triple DES: Encryption Algorithms Explained
An educational overview of symmetric encryption algorithms, their security levels, key sizes, and when to use each one in modern applications.
Cryptographic Hash Functions: SHA-256, MD5, and Beyond
An in-depth guide to hash functions covering SHA-256, SHA-3, MD5, BLAKE3, and their applications in file integrity, passwords, digital signatures, and blockchain.