Base64 Encode/Decode Image support

Encode and decode text to Base64. For API integration and data transfer.

About this tool

This tool encodes and decodes text to Base64 in one click. Three features: 1) Toggle encode/decode with one click, 2) Supports Unicode (UTF-8) including Japanese, 3) All processing in browser—no data sent to server. Ideal for Basic auth headers and Data URI generation.

Tool interface

Usage

  1. Enter text in the input field
  2. Click Encode for Base64 or Decode to restore
  3. Supports Unicode including Japanese

When to use

Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.

Examples

Hello → SGVsbG8=, embed image as Data URI in HTML.

Tips

  • Basic auth: Authorization: Basic + Base64(user:pass).
  • Data URI: data:image/png;base64, + Base64(image).
  • All processing is local. No data sent to server.

FAQ

What is Base64?

Encoding that represents binary as 64 ASCII chars (A-Z, a-z, 0-9, +, /). Lets you handle images/files as text for email, Data URIs, etc.

Can Base64 handle Japanese?

Yes. Encode to UTF-8 first, then Base64. This tool supports Unicode including Japanese.

What is Data URI?

Format to embed images in HTML/CSS with data: scheme. data:image/png;base64, followed by Base64 string. No external file, but not cached.

Benefits of Base64 encoding?

Binary as text for JSON/API transfer, safe in email, can be URL-safe. Good for small images and auth headers.

Invalid character in base64 string error

Input contains invalid chars (spaces, newlines, or prefixes like data:image/png;base64,). Use only Base64 chars (A-Za-z0-9+/=). For Data URI, paste only the part after the comma.

Failed to execute 'atob' error

atob is the browser API for Base64 decode. Invalid Base64 input causes this. Remove extra characters and retry.

Is Base64 Encode/Decode free?

Free to use, no sign-up required.

Is data sent to a server?

Data stays on your device; we do not store it on our servers.

Supported browsers?

Tested on recent Chrome, Edge, Firefox, and Safari.

Offline use?

Core features work offline after the first load.

vs CLI or desktop apps?

Base64 Encode/Decode is an install-free online alternative to CLI or desktop apps.

When to use it?

Use it when: Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.

Usage example?

Example: Hello → SGVsbG8=, embed image as Data URI in HTML.

Main features?

Base64 encode and decode, Unicode support, Data URI generation

How is this different from similar tools?

Base64 Encode/Decode runs in the browser with no install—ideal for quick checks before heavier CLI or IDE workflows.

Search keywords

Base64, 画像, 画像埋め込み, Data URI, 変換方法, エンコード, Base64 Decode, Base64 Encode, img-to-base64, binary-to-text, Data URI, image to base64

Basic workflow

  1. Enter text in the input field
  2. Click Encode for Base64 or Decode to restore
  3. Supports Unicode including Japanese

Practical use cases

  • Basic auth headers, Data URIs (image embedding), API payload transfer, binary as text.
  • This tool encodes and decodes text to Base64 in one click. Three features: 1) Toggle encode/decode with one click, 2) Supports Unicode (UTF-8) including Japanese, 3) All processing in browser—no data sent to server. Ideal for Basic auth headers and Data URI generation.
  • Basic auth: Authorization: Basic + Base64(user:pass).
  • Data URI: data:image/png;base64, + Base64(image).
  • All processing is local. No data sent to server.
  • Base64 encode and decode
  • Unicode support

Privacy & data handling

Data stays on your device; we do not store it on our servers.

Things to watch out for

  • Always double-check before pasting output into production
  • Try incognito if extensions break the page
  • Wait for processing on large inputs

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Tool set

Encode & Convert Set