Base64エンコーダー - 安全なデータエンコード
ツールに戻るAbout Base64 Encoding
テキスト、URL、バイナリデータを安全な送信のためにBase64形式にエンコード。メールシステム、JSON API、データストレージで広く使用。CSSやHTMLへの画像埋め込みに最適。
Key Features
- Instant text to Base64 conversion
- Safe for email and web transmission
- Handles special characters and binary data
- Copy results with one click
Common Use Cases
- API authentication headers
- Email attachment encoding
- Data URLs for images in CSS/HTML
- JSON data transmission
Security Note: Base64 is encoding, not encryption. Do not use for sensitive data protection.
Base64 Encoding Examples
Simple Text Encoding
入力:
Hello World!出力:
SGVsbG8gV29ybGQhURL Encoding
入力:
https://example.com/path?param=value出力:
aHR0cHM6Ly9leGFtcGxlLmNvbS9wYXRoP3BhcmFtPXZhbHVlJSON Data Encoding
入力:
{"name":"John","age":30}出力:
eyJuYW1lIjoiSm9obiIsImFnZSI6MzB9Basic Auth Credentials
入力:
username:password出力:
dXNlcm5hbWU6cGFzc3dvcmQ=How Base64 Works
- Convert input to binary (8-bit bytes)
- Group binary into 6-bit chunks
- Map each 6-bit value to Base64 alphabet
- Add padding (=) for alignment
Base64 Character Set
A-Z, a-z, 0-9, +, /, =
Professional Use Cases
Web Development
- Embedding images in CSS (data URLs)
- Storing binary data in JSON
- Email template inline images
API Development
- Basic authentication headers
- Binary data in REST APIs
- File upload preprocessing
Tips and Best Practices
Best Practices
- Always validate Base64 strings before processing
- Use URL-safe Base64 for web applications
- Consider performance impact on large files
Common Mistakes
- Using Base64 for password security
- Not handling padding correctly
- Ignoring character encoding issues