Uses btoa() and atob() with proper UTF-8 handling via TextEncoder/TextDecoder. Important distinction because vanilla Base64 chokes on emoji and non-ASCII characters—this one doesn't. Standard Base64 and URL-safe variants (swaps + and / for - and _), depending on whether you're putting it in a URL or not.
Base64 Encoder/Decoder
Encode and decode text and images to Base64 instantly. No signup, 100% private. Your data never leaves your browser. Part of comprehensive free toolkit.
Output...
Frequently Asked Questions
Quick answers to common questions
What is Base64 encoding?
Base64 is a binary-to-text encoding scheme that represents binary data in an ASCII string format. It's commonly used to encode data for transmission over networks designed to handle text.
How do I encode text to Base64?
Simply enter your text or upload a file in the input area and click the 'Encode' button. The tool will instantly convert your content to Base64 format.
Can I encode images to Base64?
Yes! You can upload images (PNG, JPG, GIF, SVG) and the tool will convert them to Base64 strings that can be used in HTML img tags or CSS background images.
Is Base64 encoding secure?
Base64 is an encoding method, not encryption. It's designed for safe data transmission, not for securing sensitive information. Encoded data can be easily decoded.
What is the difference between Base64 and Base64URL?
Base64URL is a variant of Base64 that replaces '+' and '/' characters with '-' and '_' respectively, making it safe for use in URLs and filenames without needing URL encoding.
View Complete Guide & Tutorials
Explore advanced techniques and best practices
Use Cases
Discover how to integrate this tool into your workflow
Data Transmission
Encode binary data for safe transmission over text-based protocols.
- Email attachments encoding
- XML/JSON data embedding
- URL parameter encoding
- API request formatting
Web Development
Work with Base64 encoded images and resources in web applications.
- Embed images in HTML/CSS
- Data URI creation
- SVG optimization
- Font embedding
Authentication
Handle HTTP Basic Authentication and authorization headers.
- Basic auth header generation
- Credential encoding
- Token decoding
- API authentication setup
About This Tool
Base64 encoding is one of those things I always have to Google because I can never remember the exact syntax. This tool handles it—paste your text, get Base64. Decode it back? Also here. Useful for embedding images in CSS, handling API credentials, or whenever something needs to be ASCII-safe. Fun fact: most "encrypted" data you see in URLs is actually just Base64.
Technical Details
Algorithm
Pretty straightforward: groups 3 bytes into 4 characters using a 64-character set (A-Z, a-z, 0-9, +, /). Padding with = at the end if needed. URL-safe version just replaces two characters to avoid URL encoding issues. One of those encoding schemes that's simple once you get it, annoying to memorize—hence this tool.
Privacy Commitment
🔒 **Privacy First**: Unlike server-based tools, AI-TOL processes everything locally in your browser - your data never leaves your device. No uploads, no tracking, completely private.