What Is Base64 Decoding?
Base64 decoding reverses the binary-to-text encoding process, converting a string made up of 64 printable ASCII characters (A–Z, a–z, 0–9, + and /) back into its original text or binary form. It is the counterpart to Base64 encoding, commonly used when receiving data from email, URLs, or JSON payloads.
This tool converts any Base64 string you type or paste back into its original text instantly, entirely inside your browser — nothing is uploaded or stored.
How to Use the Base64 Decoder
- Type or paste the Base64 string you want to decode into the input field.
- The decoded text appears automatically below.
- Click "Copy" to copy the decoded result to your clipboard.
Frequently Asked Questions
Is it safe to decode sensitive Base64 strings here?
Yes. All decoding happens locally in your browser using JavaScript — your data is never sent to a server.
What happens if I enter an invalid Base64 string?
The tool detects invalid input and shows a warning message. Make sure your string only contains valid Base64 characters and correct padding.
Does it support Unicode characters and emoji?
Yes, the decoder correctly reconstructs Unicode text, including emoji and non-Latin scripts, by interpreting the decoded bytes as UTF-8.