🔐 Base64 Encoder & Decoder

Encode text to Base64 or decode Base64 to text instantly • Free online tool • No signup required

Plain Text Input
Base64 Output

What is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that converts binary data into ASCII text format. It's commonly used to encode data that needs to be transmitted over text-based protocols like email, HTTP, or stored in JSON and XML files. Base64 encoding ensures that binary data remains intact without modification during transport.

Why Use Base64 Encoding?

Base64 encoding is essential in web development and data transmission:

  • Email Attachments - MIME protocol uses Base64 to encode binary attachments
  • Data URLs - Embed images directly in HTML/CSS using Base64 data URIs
  • API Authentication - Basic HTTP authentication encodes credentials in Base64
  • JSON/XML Transport - Send binary data through text-only formats
  • URL Parameters - Safely transmit binary data in URLs
  • Database Storage - Store binary content in text fields

How to Use Base64 Encoder/Decoder

Our Base64 tool makes encoding and decoding simple:

  1. To Encode: Enter or paste your text in the input field and click "Encode to Base64"
  2. To Decode: Paste Base64-encoded text and click "Decode from Base64"
  3. Upload Files: Use the file upload button to encode entire files to Base64
  4. Copy/Download: Copy the result to clipboard or download as a text file
  5. Clear: Reset both input and output fields to start fresh

Base64 Encoding Examples

Example 1: Text Encoding

Original Text:

Hello, World!

Base64 Encoded:

SGVsbG8sIFdvcmxkIQ==

Example 2: Email/Password Encoding (HTTP Basic Auth)

Original Text:

user@example.com:mypassword

Base64 Encoded:

dXNlckBleGFtcGxlLmNvbTpteXBhc3N3b3Jk

Used in HTTP Header:

Authorization: Basic dXNlckBleGFtcGxlLmNvbTpteXBhc3N3b3Jk

Example 3: Data URL for Image

Base64 Encoded Image (small PNG):

data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAAUA...

This can be used directly in HTML <img> tags or CSS backgrounds.

Common Base64 Use Cases

  • Web Development - Embed small images in CSS/HTML without separate HTTP requests
  • API Integration - Send binary files through JSON APIs
  • Email Systems - Attach files to emails using MIME encoding
  • Authentication - HTTP Basic Auth encodes username:password in Base64
  • Configuration Files - Store credentials or certificates in text config files
  • Database Storage - Store binary content in VARCHAR/TEXT fields
  • Cryptography - Represent encrypted data in readable format

Base64 Character Set

Base64 uses 64 characters to represent binary data:

  • Letters: A-Z (uppercase), a-z (lowercase) = 52 characters
  • Numbers: 0-9 = 10 characters
  • Symbols: + and / = 2 characters
  • Padding: = (used at the end when needed)

Base64 vs Other Encoding

EncodingCharactersUse CaseSize Increase
Base64A-Z, a-z, 0-9, +, /General purpose, email, APIs~33%
Base64 URL-SafeA-Z, a-z, 0-9, -, _URL parameters, filenames~33%
Hex (Base16)0-9, A-FHashes, colors, debugging100%
ASCII0-127Plain text only0%

Is Base64 Encryption?

No! Base64 is encoding, not encryption. It transforms data format but provides zero security. Anyone can decode Base64 instantly. Never use Base64 alone to protect sensitive data. For security, use proper encryption (AES, RSA) before Base64 encoding.

Base64 in Web Development

Developers use Base64 encoding in various scenarios:

  • CSS Background Images: background: url(data:image/png;base64,...);
  • HTML Images: <img src="data:image/png;base64,..." />
  • JavaScript: btoa() encodes, atob() decodes
  • Node.js: Buffer.from(str).toString('base64')
  • HTTP Headers: Authorization headers for API authentication

Privacy and Security

All Base64 encoding and decoding happens directly in your browser. Your data never leaves your device and is not stored on any server, ensuring complete privacy and security. This tool works entirely offline after the page loads.

🔐 Encode Text

Convert plain text to Base64 format instantly with proper padding.

🔓 Decode Base64

Decode Base64 strings back to readable text with validation.

📁 File Support

Upload files and encode them to Base64 for embedding or transmission.

⚡ Instant Results

Real-time encoding and decoding as you type or upload files.

Frequently Asked Questions

What is Base64 used for?

Base64 is used to encode binary data into ASCII text format for transmission over text-based protocols like email (MIME), HTTP, JSON, and XML. It's commonly used for embedding images in HTML/CSS, API authentication, and storing binary data in text fields.

Is Base64 encoding secure?

No, Base64 is not a security or encryption method. It's an encoding scheme that makes data format-compatible but provides no confidentiality. Anyone can decode Base64 data instantly. Use proper encryption (AES, RSA) if security is needed.

Why does Base64 increase file size?

Base64 encoding increases file size by approximately 33% because it represents 3 bytes of binary data using 4 ASCII characters. This overhead is the trade-off for making binary data text-compatible.

Can I decode Base64 without special tools?

Yes, you can decode Base64 using built-in browser JavaScript (atob() function) or command-line tools like base64 -d in Linux/Mac. However, online tools like ours provide a more user-friendly interface.

What does the "=" padding mean in Base64?

The "=" character is padding added at the end of Base64 strings to make the length a multiple of 4. It indicates how many bytes were in the original data. One "=" means the last group had 2 bytes, two "==" means it had 1 byte.