What is Base64 Encoding?

Base64 is a binary-to-text encoding scheme that turns binary data into an ASCII string format using a set of 64 characters. These include:

A-Z, a-z, 0-9, +,

Padding with = is used if the data doesn’t fill up the required 24-bit chunks. It’s not encryption — just a safe way to encode data for text-based transmission.

How Base64 Encoding Works

1. Binary Conversion: The input text or file is first converted into its binary representation.

2. Chunking: Binary data is divided into 6-bit segments.

3. Mapping: Each 6-bit segment is mapped to a character in the Base64 index table.

4. Padding: If the last chunk is less than 24 bits, = padding is added to make it valid.

How to Encode Using Base64 in Practice

Example 1: Encoding a Text String

Input:

Hello

Binary Representation:

01001000 01100101 01101100 01101100 01101111

Base64 Output:

SGVsbG8

Example 2: Encoding a JSON Payload

JSON Input:

{"user":"kavya","role":"admin"}

Base64 Output:

eyJ1c2VyIjoia2F2eWEiLCJyb2xlIjoiYWRtaW4ifQ

Example 3: Encoding an Image (binary)

A .png file encoded in Base64 can be used in HTML as:

<img src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUg...">

Use Cases

• Embedding images in HTML/CSS via data: URIs

• Sending files or payloads in APIs where binary is not allowed

• Storing small files in databases or text-based formats

• Email attachments encoded as MIME Base64

Pro Tips

• Shorten Payloads: Base64 increases size by ~33%. Avoid overusing for large files.

• Use UTF-8 before encoding multilingual content. Try our UTF8 Encoder to prepare data.

• Combine with Decoder: Pair with our Base64 Decoder for round-trip conversions.

• Escape Safely: For use in URLs, use a URL Encoder afterward to escape +, /, and =.