Text & Encoding / letter transformations
AES Hex Calculator
Encrypt and decrypt hex data with a 128, 192, or 256-bit AES key in ECB mode, with every SubBytes, ShiftRows, MixColumns, and AddRoundKey step shown.
Answer first
How do I use a AES hex encryption and decryption calculator?
Encrypt and decrypt hex data with a 128, 192, or 256-bit AES key in ECB mode, with every SubBytes, ShiftRows, MixColumns, and AddRoundKey step shown. Enter the known values and inspect the result immediately. For example, Encrypt hex block 00112233445566778899aabbccddeeff with the FIPS-197 test key 000102030405060708090a0b0c0d0e0f to get 69c4e0d86a7b0430d8cdb78070b4c55a. Use the output to check your reasoning or shortlist a design, then verify the units, assumptions, and real-world limits that apply.
Round-by-round state (first block)
Every SubBytes, ShiftRows, MixColumns, and AddRoundKey transformation applied to the first 16-byte block.
AES (Advanced Encryption Standard)
AES encrypts 16-byte blocks with a key of 128, 192, or 256 bits, running 10, 12, or 14 rounds of SubBytes (a fixed non-linear substitution), ShiftRows (cyclic row shifts), MixColumns (a linear mix within each column), and AddRoundKey (XOR with a key derived for that round). Decryption runs the inverse steps in reverse order.
This is a from-scratch, unaudited AES implementation for learning ECB-mode block mechanics, not a cryptographic library. Do not use it to protect real secrets - use a vetted library (Web Crypto, OpenSSL) for anything that matters, and never use ECB mode in production (it leaks patterns between identical blocks).
Design guide
Use the result with engineering context
Technical content reviewed
When this tool is useful
- Solving a AES hex encryption and decryption calculator task without repeating the arithmetic by hand
- Changing one input at a time to understand how it affects the result
What the result includes
- A result calculated from the values and units you enter
- A concrete reference case: Encrypt hex block 00112233445566778899aabbccddeeff with the FIPS-197 test key 000102030405060708090a0b0c0d0e0f to get 69c4e0d86a7b0430d8cdb78070b4c55a.
What the model does not guarantee
- The result depends on the selected width, alphabet, encoding, and input format
- Encoding and number conversion do not provide encryption, authentication, or protection for sensitive data
Worked approach
Try a concrete set of values
Encrypt hex block 00112233445566778899aabbccddeeff with the FIPS-197 test key 000102030405060708090a0b0c0d0e0f to get 69c4e0d86a7b0430d8cdb78070b4c55a. Change one input at a time, confirm the units, and compare the result with an independent calculation or relevant datasheet.
Common decisions
Questions engineers ask
What should I enter in the AES Hex Calculator?
Use known values in the units shown beside each field. Keep every input within a realistic range and convert units before comparing the result with another source.
Can I use the AES Hex Calculator result directly?
Encoding and number conversion do not provide encryption, authentication, or protection for sensitive data
How should I verify the AES Hex Calculator result?
Repeat the worked example, check the units and assumptions, then compare the output with a second calculation, a trusted reference, or a measurement from the real system.
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