Base64

Professional Base64 encoding and decoding tool supporting UTF-8 text and Base64 string conversion. Ideal for data transmission, API development, image embedding and more.

What You Can Do With It?

Embed Images in HTML

Convert images to Base64 and inline them in HTML/CSS with no extra requests

Debug API Auth Headers

Decode Base64 credentials in Authorization headers to troubleshoot auth issues

Decode Email Attachments

Decode MIME Base64 attachment data to inspect raw file content

Transfer Binary Data

Encode files as Base64 strings to safely embed in JSON or XML payloads

Optimize Frontend Assets

Inline small icons as Base64 to reduce HTTP requests and improve load speed

Automate CI/CD Encoding

Quickly verify Base64 encode/decode logic in automation scripts and pipelines

How To Use?

1

Input Content

Paste text or upload a file into the input area

2

Choose Direction

Click Encode or Decode to perform the conversion

3

Copy the Result

Copy the output with one click and paste it wherever needed

Related Tools

Frequently Asked Questions

Yes. This tool uses TextEncoder/TextDecoder for UTF-8 safe Base64 encoding and decoding, correctly handling Chinese, emoji and other Unicode characters.

Encountered other problems or suggestions? Have a bug or suggestion? Drop us an email.

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Why Developers Need a Base64 Encoder/Decoder in 2026

Base64 is an encoding scheme that converts binary data into ASCII strings, and it is used extensively in web development. From passing authentication tokens in API requests and embedding images in HTML via Data URIs, to processing email attachments and JSON Web Tokens (JWT), Base64 encoding is virtually ubiquitous.

In 2026, frontend-backend interactions are increasingly complex, and Base64 scenarios continue to multiply. Debugging APIs requires decoding Base64 request bodies, handling OAuth tokens means inspecting encoded payloads, and email system development involves encoding and decoding attachments. A convenient Base64 tool significantly boosts efficiency in all these tasks.

MeTool's Base64 encoder/decoder supports bidirectional conversion between UTF-8 text and Base64. All encoding and decoding operations run entirely in your browser — your sensitive data such as tokens and keys never passes through any external server, ensuring complete information security.

Key Features of MeTool Base64 Tool

Instant Bidirectional Conversion

Switch seamlessly between text-to-Base64 encoding and Base64-to-text decoding. Simply toggle the mode, and results appear in real time — no page reloads or separate tools needed.

Full UTF-8 Support

Handles multi-byte characters including Chinese, Japanese, Korean, and emoji flawlessly. No garbled output or encoding errors, ensuring correct processing for internationalized content.

Optimized for Data Transmission

Designed for common developer scenarios: encoding API authentication headers, creating Data URI image embeds, and parsing JWT token payloads. Each use case is handled smoothly out of the box.

Secure Local Processing

All encoding and decoding happens entirely in your browser — data is never uploaded to any server. This is especially critical when handling strings that contain keys, tokens, or personally identifiable information.

How to Use MeTool Base64 Encoder/Decoder

  1. Open the Tool: Navigate to MeTool's Base64 page — no login required to start using it.
  2. Select Mode: Choose "Encode" (text → Base64) or "Decode" (Base64 → text) depending on your need.
  3. Enter Content: Paste or type your text or Base64 string in the input area. The conversion result appears in real time.
  4. Copy the Result: Click the copy button to place the output on your clipboard, ready to use in your code, API requests, or configuration files.