Base64 编码器/解码器
编码和解码 Base64 字符串
什么是 Base64？
Base64 是一种二进制到文本的编码方案，以 ASCII 字符串格式表示二进制数据。它通常用于对数据进行编码，以便在只支持文本内容的媒体上传输。
使用案例
- 电子邮件附件 - HTML/CSS 中的数据 URL - API 标记编码 - 在 JSON/XML 中存储二进制数据
What is Base64 Encoding?
Base64 is a binary-to-text encoding scheme that represents binary data in ASCII string format. It uses 64 characters (A-Z, a-z, 0-9, +, /) to represent binary data, making it safe for transmission over text-based protocols.
Email Attachments
MIME encoding for email attachments
Data URIs
Embed images directly in HTML/CSS
API Communication
Encode binary data in JSON/XML
Authentication
HTTP Basic Authentication headers
How to Use the Base64 Converter
Text Encoding/Decoding:
- Enter your text in the input field
- Click "Encode" to convert text to Base64
- Click "Decode" to convert Base64 back to text
- Use "Swap" to exchange input and output
Image Conversion:
- Click "Upload Image" to select an image file
- The Base64 data URI will be generated automatically
- Paste a Base64 string and click "Preview" to view as image
- Copy the Base64 string for use in your code
Frequently Asked Questions
Why use Base64 encoding?
Base64 is essential when you need to transfer binary data through text-based protocols that don't support binary. It's commonly used in emails, data URIs, and API payloads.
Is Base64 encryption?
No, Base64 is encoding, not encryption. It doesn't provide any security - anyone can decode Base64 data. Use proper encryption if security is needed.
Why is Base64 output larger than input?
Base64 encoding increases data size by approximately 33% because it uses 4 characters to represent every 3 bytes of input data.
Is my data secure?
Yes! All encoding and decoding happens locally in your browser. Your data is never sent to any server.