Base64 Decoder
Decode Base64 strings back to readable text instantly
Decoded text will appear here
Quick Examples
What is Base64 Decoding?
Base64 decoding is the process of converting Base64 encoded text back to its original format. When data is Base64 encoded, it's converted into a specific set of 64 ASCII characters (A-Z, a-z, 0-9, +, /). Decoding reverses this process, restoring the original text, binary data, or other content.
This tool helps you decode Base64 strings that you might encounter in API responses, HTTP headers, configuration files, or data URIs. Simply paste the encoded string, and it will instantly convert it back to readable text, revealing the original content.
Base64 decoding is essential for developers who need to inspect encoded data, debug API responses, or understand what's contained in encoded strings they receive from various sources.
When Do You Need Base64 Decoding?
Debugging API Responses
Decode Base64 encoded data returned by APIs to inspect actual values and troubleshoot issues
Reading Encoded Credentials
Decode HTTP Basic Authentication headers to extract username and password combinations
Analyzing JWT Tokens
Decode JWT token payloads to inspect claims, expiration times, and user information
Extracting Data URI Content
Decode data URIs to extract embedded images, fonts, or documents from HTML/CSS
Reading Configuration Files
Decode Base64 encoded values in configuration files, environment variables, or secrets
Understanding Input Formats
Standard Base64
Decodes standard Base64 that uses + and / characters, with = padding. This is the most common format you'll encounter.
Example: SGVsbG8sIFdvcmxkIQ==
URL-Safe Base64
Decodes URL-safe Base64 that uses - instead of + and _ instead of /. Often found in URLs, JWT tokens, and file names.
Example: SGVsbG8sIFdvcmxkIQ (no padding)
Common Decoding Scenarios
| Scenario | Example Input | Output |
|---|---|---|
| HTTP Basic Auth | dXNlcjpwYXNzd29yZA== | user:password |
| Simple Text | SGVsbG8h | Hello! |
| JSON Data | eyJ0ZXN0Ijp0cnVlfQ== | "test":true |
| Unicode/Emoji | 8J+YgA== | 😀 |
Frequently Asked Questions
Can I decode any Base64 string?
You can decode any valid Base64 string. However, if the string is malformed or contains invalid characters, you'll see an error. Make sure your input is properly Base64 encoded and choose the correct format (Standard or URL-safe).
What if I get gibberish after decoding?
If the decoded output looks like gibberish or strange characters, it might be binary data (like an image or file) rather than text. Base64 is often used to encode binary data, which won't display as readable text when decoded.
Is decoding Base64 the same as decryption?
No! Base64 decoding is NOT decryption. Base64 is simply an encoding scheme to represent binary data as text. Anyone can decode Base64 - no key or password is needed. It provides zero security. Never assume Base64 encoded data is secure.
Can I decode JWT tokens?
Yes! JWT tokens are made of three Base64-URL-safe encoded parts separated by dots. You can decode the header and payload sections (the first two parts) to inspect claims, user data, and expiration times. The third part is the signature and won't decode to readable text.
Does this tool handle line breaks?
Yes! The tool automatically removes all whitespace and line breaks before decoding. You can paste Base64 strings with MIME-style line breaks (76 characters) or any other formatting, and it will decode correctly.
Is my data safe using this tool?
Absolutely! All decoding happens entirely in your browser using JavaScript. No data is sent to our servers or any third party. Your encoded input and decoded output remain completely private on your device.
Important Security Note
Base64 is NOT encryption! It's simply an encoding format. Anyone can decode Base64 data instantly without a key or password. Never use Base64 alone to protect sensitive information. Always use proper encryption (like AES-256) for securing data.