Base64 Decoder
Decode Base64 strings back into readable plain text with UTF-8 character support.
Run tool
This online Base64 decoder converts encoded ASCII strings back into standard readable text. When you paste encoded content into the input field, the tool interprets the decoded byte stream using UTF-8 character encoding. This process handles standard alphanumeric characters as well as international symbols, accented letters, and multi-byte characters such as emojis. If the incoming payload contains malformed byte sequences that do not map cleanly to standard UTF-8 characters, those invalid segments are replaced with standard replacement markers so you can inspect the remaining readable text without total decoding failure. The interface requires a non-empty string to initiate decoding, making it practical for inspecting API tokens, debugging authorization headers, parsing configuration data, or verifying payload strings. You can run immediate conversions directly in your browser window and copy the decoded output for use in development files, terminal scripts, or documentation.
Instructions
- Paste or type your Base64-encoded string into the Base64 text input box.
- Click the decode button to process the encoded string.
- Inspect the resulting readable plain text in the output area.
- Copy the decoded UTF-8 text for use in your code, terminal, or documents.
Examples
- Decoding standard text: Entering 'SGVsbG8sIFdvcmxkIQ==' produces 'Hello, World!' in the output panel.
- Decoding international text: Entering '0JfQtNGA0LDQstGB0YLRg9C5LCDQvNC40YAh' produces 'Здравствуй, мир!' in the output panel.
FAQ
What happens if the input field is left empty?
The tool requires a non-empty input to run. Submitting an empty field will not produce decoded text.
How are international characters and symbols handled?
The decoded bytes are interpreted using UTF-8, allowing multi-byte scripts, accented letters, and symbols to display properly.
What happens if the input contains corrupted or non-standard bytes?
Any byte sequence that cannot be interpreted as valid UTF-8 is substituted with standard replacement characters instead of stopping the process.
Can I decode strings produced by the Base64 encoder tool?
Yes, text encoded with the companion Base64 encoder decodes directly back to the original text.