Utilities Web
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Base64 Encode/Decode

Base64 conversion of text and files

How to Use

  1. Enter the text string you want to convert in the text input field
  2. Click the "Encode" or "Decode" button
  3. The conversion result is displayed in the output field
  4. You can copy it to the clipboard with the "Copy" button
  5. Base64 conversion of files is also possible from "Select File"

Use Cases

  • Encoding when including binary data in API requests
  • When embedding images in HTML/CSS using Data URI scheme
  • When checking MIME encoded content of email attachments
  • When decoding the payload of authentication tokens (such as JWT) to check the contents

Frequently Asked Questions

What is Base64 encoding? ▼

Base64 is an encoding method that converts binary data into ASCII character strings. It expresses data using 64 types of characters: A-Z, a-z, 0-9, +, and /. It is widely used in situations where binary data cannot be directly handled, such as in emails and URLs.

Can I Base64 encode Japanese text? ▼

Yes, this tool fully supports UTF-8. You can Base64 encode and decode any text including Japanese.

Is the input data sent to a server? ▼

No, all processing is completed on the browser. Input data is never sent to the outside. Please use it with confidence.

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