Instantly translate Base64 encoded strings back into readable text or downloadable files.
Decode Base64 encoded strings back to plain text.
The Base64 Decoder takes any valid Base64 encoded string and translates it back into plain text, including handling Unicode characters correctly.
SGVsbG8gV29ybGQ=Hello WorldRuns instantly on your local device.
No files are ever stored or uploaded.
Works perfectly on any screen size.
Delivers professional-grade output.
Use it on Chrome, Safari, or Edge.
Unlimited usage with no hidden fees.
Get results in seconds with our streamlined, browser-native process.
Paste the obfuscated Base64 string or Data URI directly into the translation field.
Specify whether you expect the output to be human-readable text or a raw binary file.
The engine strips prefixes, calculates padding, and maps the ASCII characters back to their raw byte values.
Read the translated text directly in the console or download the reconstructed file to your local system.
Designed to save time, protect your privacy, and deliver professional-grade results every time.
Automatically detects MIME types and handles Data URI prefixes to prevent structural corruption during extraction.
Capable of rebuilding raw binary structures, allowing you to download decoded images, PDFs, or audio files directly.
Features robust error handling that attempts to resolve missing padding syntax or invalid characters in dirty strings.
Maintains absolute data sovereignty by executing the reverse-translation entirely within your machine's browser memory.
See how different professionals leverage this tool in their daily workflows.
Decode the payload section of JSON Web Tokens to rapidly verify user claims, expiration dates, and authorization scopes.
Safely unpack obfuscated strings found in suspicious scripts or log files to understand malicious payload intentions.
Extract and rebuild documents or images that were stored directly as Base64 strings inside legacy SQL database columns.
Reverse Basic Auth headers from network requests to verify that client applications are transmitting the correct credentials.
Why thousands choose our platform over traditional software.
Everything you need to know about this tool.
The parser initially attempts to decode the string using UTF-8 mapping. If it encounters raw byte structures that fall outside printable text ranges, it provides the option to output and download the raw binary file instead.
Yes, the engine automatically detects and strips out standard prefixes (e.g., 'data:image/png;base64,') before processing the core string, preventing corruption in the final output.
The tool features a resilient parser that can intelligently append missing '=' padding characters to malformed strings, attempting a best-effort recovery of the data.
Absolutely. The entire decoding algorithm runs strictly on the client side. The data is processed in your device's memory and is never transmitted to our servers.
The tool performs a single pass per execution. If a string was encoded multiple times, you will need to copy the resulting output and feed it back into the decoder recursively.
This typically happens if the original source was actually a binary file (like an image or zip archive) rather than a text string. You should switch the output mode to 'File Download'.
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