Online Base64 & URL Encoder/Decoder
This 100% free, private tool allows you to instantly encode and decode Base64 strings and URLs directly in your browser. With no server uploads required, it is the safest way to convert sensitive strings and debug web tokens offline. If you need to generate secure UUIDs, check out our UUID Generator.
What is Base64 Encoding?
Base64 encoding translates binary data or standard text into a 64-character ASCII string format. It is used to safely transmit data across channels that only reliably support text content, such as email attachments or embedding image data directly into CSS/HTML files.
Example
Input (Text):
Hello World
Output (Base64):
SGVsbG8gV29ybGQ=
Advantages and Limitations
- Advantages: Prevents data corruption during text-based transmission, completely offline for privacy, and instantaneous processing.
- Limitations: Base64 increases the data size by approximately 33%. It is an encoding method, not encryption, meaning the data is not secure against unauthorized viewing.
How to Use
- Paste your text, Base64 string, or URL into the "Input Text" box.
- Click the appropriate encode or decode button for Base64 or URL format.
- The converted string will instantly appear in the "Output Result" box.
- Click "Copy" to save the result to your clipboard.
Common Use Cases
- API Development: Encoding API keys or Basic Authentication headers into Base64 format before sending HTTP requests.
- Data Debugging: Decoding JSON Web Tokens (JWTs) or email attachments to inspect their payloads. For inspecting JSON structures within decoded JWTs, try our JSON Formatter.
- URL Parsing: Encoding query parameters to ensure special characters like '&' and '=' are transmitted safely in web links.
Privacy & Security
Your data privacy is our top priority. This tool relies on local browser APIs (like `btoa` and `atob`) to perform all encoding and decoding entirely offline. Your strings are never logged, stored, or transmitted over the internet.
Frequently Asked Questions
What is Base64 encoding used for?
Base64 is used to convert binary data into a readable ASCII text format. It is commonly used for embedding images in HTML/CSS, sending email attachments, and transmitting basic authentication credentials.
Is Base64 encoding the same as encryption?
No. Base64 is merely a data format encoding, not a security encryption. Anyone with a Base64 decoder can easily read the data, so it should never be used to hide sensitive information without actual encryption.
Why do I need to URL encode text?
URLs can only be sent over the internet using the ASCII character set. URL encoding converts unsafe characters (like spaces or symbols) into a valid format (like %20 for space) so web servers can process them correctly.