AES Encryption & Decryption (Web Crypto)
AES Encryption & Decryption (Web Crypto) — PBKDF2-HMAC-SHA256 derives a 32-byte key with 120000 iterations and a 16-byte salt. AES-GCM uses a 12-byte IV and appends its 16-byte authentication tag to the ciphertext before Base64 encoding.
About this aes encryption & decryption (web crypto)
AES Encryption & Decryption (Web Crypto) — browser-based utility.
How this tool works
Implements client-side AES Encryption & Decryption (Web Crypto) operations. Derives 256-bit key via PBKDF2-HMAC-SHA256, generates 96-bit random IV, and computes ciphertext with 128-bit GCM auth tag specifically designed for a security engineer encrypts sensitive json configuration locally using aes-256-gcm authenticated encryption.
- Key Derivation & CSPRNG Nonce Generation: Derives cryptographic keys from passphrases via PBKDF2 with random salts and generates unique IV nonces.
- Authenticated Encryption (AEAD): Encrypts plaintext blocks and computes an authentication tag to protect against ciphertext tampering.
- Container Formatting: Packages salt, IV, ciphertext, and auth tag into standardized Base64 or JSON envelopes.
- Decryption & Tamper Verification: Verifies the authentication tag before decrypting; throws immediate integrity errors if data was modified.
Worked example
Scenario: Reproduce a four-byte AES-GCM test vector. This public password, salt and IV are for this test only; never reuse this combination for real messages.
Sample input:
Processing: PBKDF2-HMAC-SHA256 derives a 32-byte key with 120000 iterations and a 16-byte salt. AES-GCM uses a 12-byte IV and appends its 16-byte authentication tag to the ciphertext before Base64 encoding.
Illustrative output:
Limits and verification
Never reuses an Initialization Vector (IV) with the same key (IV reuse in GCM mode destroys authenticity and leaks plaintext). Passphrases cannot be recovered if lost, as no backdoor or recovery key exists.
Examples demonstrate an expected workflow; they do not prove every input or every branch of an external specification. Check important results with an independent source before using them for money, security, compliance, safety, or irreversible file changes.
Browser processing boundary
Tool input is processed by code running in the browser and is not intentionally sent to a CZOA processing API. The page can still request ordinary site assets, analytics, or advertising when those services are enabled. Browser extensions and managed-device software remain outside this tool's control.
Relevant references
These references govern or help explain the format, protocol, or calculation used here. Listing a reference does not claim certification or complete implementation of every optional feature.
- NIST FIPS 197 (Advanced Encryption Standard - AES)
- NIST SP 800-38D (Recommendation for Block Cipher Modes of Operation: GCM)
Content owner: CZOA Tools · Last reviewed: 2026-09-15 · Review methodology
How to use it
- Enter, paste, or select your input data into the AES Encryption & Decryption (Web Crypto) workspace controls.
- Review available parameter fields, units, formats, or options configured for your task.
- Click the action button or observe immediate live calculations rendered in your browser runtime.
- Inspect the resulting output and any diagnostic messages, then copy or download the result if needed.
Frequently asked questions
Which AES mode does the tool use?+
Its encryption result identifies AES-256-GCM. It accepts a JSON object and derives the local key material from its configured password input.
What did the browser fixture verify?+
An encrypt request for plaintext abc and password pass returned an encrypt object with algorithm, ciphertext, IV, and salt fields.
Why do ciphertext and IV change across encryptions?+
Authenticated encryption uses fresh random values such as salt and IV, so encrypting the same plaintext with the same password normally yields different ciphertext.
Can it decrypt without all returned values?+
No. Decryption requires the matching password and the encoded values required by the implementation. Losing the IV or salt prevents reproducing the encryption context.