Base64 encoding is fundamental to web development, used for embedding images in CSS, transmitting binary data in JSON, and encoding email attachments. Our tool provides instant, secure Base64 encoding and decoding directly in your browser.
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that converts binary data into ASCII characters. It uses 64 characters (A-Z, a-z, 0-9, +, /) to represent data, making it safe for transmission in systems that only handle text. This is essential for embedding binary data in HTML, CSS, JSON, or email.
Why Use Base64 Encoding?
- Embed images directly in HTML/CSS without external files
- Transmit binary data safely through JSON APIs
- Encode credentials for Basic HTTP Authentication
- Include files in data URIs for single-file applications
- Encode email attachments (MIME)
- Store binary data in text-only databases
How to Use Base64 Encoder/Decoder
Choose Operation
Select Encode to convert to Base64, or Decode to convert from Base64.
Enter Input
Paste text, drag & drop a file, or click to browse for images.
Get Result
The encoded/decoded result appears instantly in the output panel.
Copy or Download
Copy the result to clipboard or download as a file.
Key Features
Text & File Support
Encode/decode both text strings and binary files (images, PDFs, etc.).
Data URI Generation
Automatically generate complete data URIs with proper MIME types.
URL-Safe Encoding
Option to use URL-safe Base64 (replacing + and / with - and _).
Real-Time Preview
See encoded/decoded output as you type.
File Type Detection
Automatically detects MIME type when encoding files.
Best Practices
- Base64 increases data size by approximately 33%
- Use data URIs for small images only (under 10KB) for performance
- Consider gzip compression for large Base64 payloads
- Use URL-safe Base64 for data in URLs and filenames
- Always specify MIME type in data URIs for proper browser handling
- For sensitive data, Base64 is NOT encryption - data is easily decoded
Common Use Cases
Inline Images
Embed small icons and images directly in CSS/HTML to reduce HTTP requests.
API Authentication
Encode credentials for HTTP Basic Authentication headers.
JSON Binary Data
Include binary files in JSON payloads for REST APIs.
Email Attachments
Encode files for embedding in email MIME format.
Frequently Asked Questions
Is Base64 encoding secure?
No! Base64 is encoding, not encryption. Anyone can decode Base64 strings. Never use it to hide sensitive data.
Why does Base64 make files larger?
Base64 uses 6 bits per character to represent 8 bits of data, resulting in a 33% size increase plus padding.
What's URL-safe Base64?
Standard Base64 uses + and / which have special meaning in URLs. URL-safe Base64 replaces these with - and _.
Can I decode a Base64 image?
Yes! Paste the Base64 string (with or without data URI prefix) and download the decoded image file.
Ready to Get Started?
100% browser-based. Your data never leaves your device.
Open Base64 Encoder & Decoder