You received a string of scrambled text and you need to read it. The first step is knowing which algorithm created it. AES, Caesar cipher, ROT13 and Base64 each look different and require a different approach to reverse. Once you identify the method, decryption takes seconds using the right tool.
What is text decryption?
Decryption is the process of converting encoded or encrypted text back into readable form. Encryption hides the original content using a key or rule. Decryption reverses that process using the same key or rule. You can use the online text encryption tool to both encrypt and decrypt text without installing any software.
How do you know which algorithm was used?
Look at the encrypted output. AES produces a string of seemingly random characters, often in Base64 format after encryption. Caesar cipher and ROT13 keep the same character shapes but shift the letters. Base64 encoded text usually ends with one or two equals signs (=) and uses only letters, numbers, plus signs and slashes.
How to decrypt AES text online
AES (Advanced Encryption Standard) is a symmetric algorithm. You need the same key that was used to encrypt the text. Open the text decryption tool, paste the encrypted string, select AES, enter the key and click decrypt. Without the correct key, AES decryption is not possible.
How to decode Caesar cipher and ROT13
Caesar cipher shifts each letter by a fixed number of positions in the alphabet. ROT13 is a Caesar cipher with a shift of 13. Both are reversible without a key. To decode a Caesar cipher, try each shift from 1 to 25 until the text becomes readable. ROT13 decryption is identical to encryption: apply it twice and you get the original text back.
How to decode Base64 text
Base64 is an encoding scheme, not a true encryption method. It converts binary data into a text-safe format. Decoding it is always possible without a key. Paste the Base64 string into the decryption tool, select Base64 and click decode. The original text appears instantly.
Common problems when decrypting text
- Wrong algorithm selected: the output will look like random characters. Try other options until the result makes sense.
- Incorrect key for AES: decryption will fail or produce garbage. Double-check the key used during encryption.
- Hidden characters in the encrypted string: invisible Unicode characters can corrupt the input. Use the AI hidden character remover to clean the text before decrypting.
- Truncated or modified ciphertext: if the encrypted string was copied partially, decryption will not work correctly.
If you are unsure which method was used, start with Base64 and ROT13 since they require no key. Then try Caesar shifts. AES should be the last option, as it requires the original encryption key to work.