100% Client-Side Processing

Base64 Encoder / Decoder

Encode and decode Base64 and URL-safe Base64 (base64url). UTF-8 aware, privacy-first, processed entirely in your browser.

UTF-8

Base64url replaces "+" with "-" and "/" with "_" and omits padding. Useful for URLs, JWTs, etc.

All processing is done locally in your browser. Your data never leaves your device.

How It Works

Base64 is a binary-to-text encoding that represents binary data using 64 ASCII characters. Our tool processes everything locally in your browser using native JavaScript APIs.

Step-by-Step Process:

  1. Paste your text or binary data into the input field
  2. Choose 'Encode' to convert to Base64, or 'Decode' to convert from Base64
  3. Toggle 'URL-safe' if the Base64 will be used in URLs or filenames
  4. Copy the result or download it as a file - all processing stays on your device

Use Cases

Base64 encoding is essential for web development, data transmission, and storage scenarios where binary data needs to be represented as text.

Web Development

Embed images in CSS/HTML using data URLs, store binary data in JSON/XML formats, and handle API tokens safely.

Email & Communication

Email attachments use MIME Base64 encoding to ensure binary files are transmitted correctly through text-based protocols.

URL & File Safety

Use URL-safe Base64 for web parameters, filenames, and any scenario where + and / characters could cause issues.

Data Storage

Store binary data in databases, configuration files, or any text-based storage system that doesn't support binary formats.

Privacy Promise

Your data security is our top priority. Our Base64 tool operates with complete privacy protection.

100% client-side processing - no server uploads
No data logging or tracking of your content
Works offline once the page is loaded
UTF-8 aware for proper Unicode handling
Instant results with no network delays
Open source algorithms you can verify

🔒 Your data never leaves your browser - 100% client-side processing guaranteed

Frequently Asked Questions

What is the difference between Base64 and Base64url?

Base64url is URL-safe: it replaces + with - and / with _ to avoid conflicts in URLs and filenames. This makes it perfect for web applications and file systems.

Can I encode binary files?

Yes, you can drag and drop files or paste binary content. The tool handles both text and binary data seamlessly using browser APIs.

Is my data safe?

Absolutely. All encoding and decoding happens in your browser using native JavaScript APIs. No data is uploaded to our servers or any third-party services.

Why do I see padding characters (=)?

Base64 uses = for padding to ensure the encoded string length is a multiple of 4 characters. This is required by the Base64 specification.

What happens if I try to decode invalid Base64?

The tool will detect invalid Base64 strings and show a clear error message, helping you identify and fix formatting issues.

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