Base64 Decode

Encodes text data into Base64 in real time.

Read-only

What is Base64 Decode Tool?

This tool decodes Base64-encoded text back to its original format. It's particularly useful when working with encoded data in web development, data transfer, API response analysis, and various other scenarios.

Problems This Tool Solves

  • Viewing the contents of Base64-encoded data in API responses
  • Reading Base64-formatted data received in emails or messaging systems
  • Decoding Base64-encoded data used in data transfers
  • Examining the original content of Base64 strings representing files or images

How to Use

  1. Paste your Base64-encoded string into the "Base64 Conversion Target" input field
  2. The decoded result will display in real-time as you type
  3. Adjust the "Decode by Line" option if needed
  4. Use the copy button to save the decoded result to your clipboard

Decode Options

Decode by Line

This option is convenient when processing multiple lines of Base64 data at once.

  • When enabled: Each line is treated as separate Base64-encoded data and decoded independently
  • When disabled: The entire input is processed as a single piece of Base64 data, including newlines

This option is particularly useful in scenarios such as:

  • Batch processing multiple Base64-encoded lines in log files
  • Processing CSV files containing multiple Base64-encoded data entries
  • Analyzing multiple Base64-encoded messages at once

Usage Examples

Example 1: Decoding an API Response

eyJuYW1lIjoiSm9obiBEb2UiLCJlbWFpbCI6ImpvaG5AZXhhbXBsZS5jb20iLCJyb2xlIjoiYWRtaW4ifQ==

Decoded result:

{ "name": "John Doe", "email": "john@example.com", "role": "admin" }

Example 2: Processing Multiple Lines of Base64 Data

With the "Decode by Line" option enabled, enter:

SGVsbG8gV29ybGQh
V2ViIFRvb2xCb3g=
QmFzZTY0IGRlY29kZXI=

Decoded result:

Hello World!
Web ToolBox
Base64 decoder

Technical Background

Base64 is an encoding scheme that converts binary data into ASCII strings. This allows binary data to be transmitted over protocols that can only handle text. It's commonly used in:

  • Email attachments (MIME format)
  • Data URI schemes
  • Binary data in JSON
  • Certificate and token encoding (such as JWT)

This tool uses standard Base64 algorithms to accurately restore encoded text to its original format.