Is my data uploaded anywhere?

No. All processing happens locally in your browser with no server round-trip.

Does this tool work offline?

Yes. Once the page loads, the tool runs entirely client-side and needs no network connection.

Is this real Salsa20 encryption?

Yes. It follows D. J. Bernstein's original specification and is verified against the official eSTREAM verified test vectors (including the 128/256-bit key setup and rekeyed sets) plus the Salsa20 core specification vectors, cross-checked with PyCryptodome.

What key and nonce sizes are required?

The key must be 16 or 32 bytes and the nonce exactly 8 bytes, entered as UTF-8 text; other lengths are rejected with an explicit error. Never reuse a nonce with the same key — reusing the keystream makes the plaintext recoverable.

TOOL

Salsa20 Decryptor

Decrypt Salsa20 ciphertext (Bernstein original design, eSTREAM portfolio) — a real algorithm verified against official eSTREAM test vectors. Key must be 16 or 32 bytes, nonce exactly 8 bytes, and the block counter must match the value used for encryption. Ciphertext input format follows the output format option (hex or base64). Free, private, and 100% client-side.

KeyNonceInitial counterOutput format

Input

Try an example:

Output

Local only

Recent history

No history yet

How to use

Paste the Salsa20 ciphertext (hex or base64) into the input box.
Set the same key (16 or 32 bytes) and nonce (exactly 8 bytes) used for encryption.
Set the same initial block counter and choose the matching ciphertext format.
Copy the recovered plaintext.

Frequently asked questions

Is my data uploaded anywhere?: No. All processing happens locally in your browser with no server round-trip.
Does this tool work offline?: Yes. Once the page loads, the tool runs entirely client-side and needs no network connection.
Is this real Salsa20 encryption?: Yes. It follows D. J. Bernstein's original specification and is verified against the official eSTREAM verified test vectors (including the 128/256-bit key setup and rekeyed sets) plus the Salsa20 core specification vectors, cross-checked with PyCryptodome.
What key and nonce sizes are required?: The key must be 16 or 32 bytes and the nonce exactly 8 bytes, entered as UTF-8 text; other lengths are rejected with an explicit error. Never reuse a nonce with the same key — reusing the keystream makes the plaintext recoverable.

Glossary terms

Salsa20

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