Base64 Encoder & Decoder (Offline & Private)

Encode and decode text or files to Base64 format instantly. Supports URL-safe encoding, Data URI, and image to base64 conversion. 100% free, client-side processing.

What is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that converts binary data into an ASCII string format. It represents binary data in a radix-64 representation using 64 printable characters (A-Z, a-z, 0-9, +, /). This makes it ideal for transmitting data over media designed to handle textual content, such as email bodies, HTTP parameters, or embedding binary data directly in HTML, CSS, and JavaScript files.

How to Use Base64 Encoder/Decoder

  1. For Text: Type or paste your text in the input field, then click "Encode" to convert to Base64 or "Decode" to convert from Base64
  2. For Files: Switch to the File tab, drag and drop or click to upload an image or any file
  3. Configure Options: Enable URL-safe encoding or Data URI prefix as needed
  4. Copy or Download: Copy the result to clipboard or download the decoded file

Common Use Cases

  • Data URIs: Embed images directly in HTML/CSS without external files
  • Email Attachments: Encode binary files for MIME email transmission
  • API Authentication: Encode credentials for HTTP Basic Authentication
  • JSON/XML Storage: Store binary data in text-based formats
  • URL Parameters: Pass binary data through URLs safely

Features

  • 100% Client-Side: All processing happens in your browser, no data sent to servers
  • Text & File Support: Encode/decode both text strings and file uploads
  • URL-Safe Mode: Generate Base64Url compatible strings for URLs
  • Data URI Generator: Create ready-to-use data URI strings with MIME type prefix
  • Image Preview: Visual preview of uploaded images before conversion
  • Drag & Drop: Easy file upload with drag and drop support

Frequently Asked Questions

What is Base64 encoding used for?
Base64 encoding converts binary data into ASCII text format, making it safe for transmission over text-based protocols like email, HTTP, or embedding in HTML/CSS. Common uses include embedding images in data URIs, encoding email attachments, and storing binary data in JSON or XML.
Is Base64 encoding secure?
No, Base64 is not encryption. It's simply an encoding format that converts binary data to text. Anyone can decode Base64 data without a key. For security, use proper encryption algorithms like AES.
What is URL-safe Base64?
URL-safe Base64 replaces '+' with '-' and '/' with '_' to make the encoded string safe for use in URLs and filenames without additional encoding.
Can I convert images to Base64?
Yes! Simply drag and drop or upload an image file, and the tool will convert it to a Base64 string with an optional Data URI prefix (e.g., data:image/png;base64,...).