Base64
Encode and decode Base64
Encode and decode Base64 instantly. Enter text to encode or a Base64 string to decode. Free tool—no signup. Perfect for developers, APIs, or data transfer. Works in your browser, private by design.
Base64 encoding converts binary data into ASCII text for safe transmission. APIs often require Base64 for images or files in JSON. Data URIs use Base64 to embed images in HTML or CSS. Email attachments are Base64-encoded. Our free tool encodes and decodes instantly. Paste text to encode, or paste Base64 to decode. Switch between modes with one click. No signup, no limits. Everything runs in your browser—we never see your data. Perfect for developers, APIs, or anyone working with encoded strings. Base64 is a standard encoding scheme that represents binary data using 64 ASCII characters. It increases size by about 33% but ensures compatibility with systems that only handle text. Web developers use it daily for inline images, API payloads, and data storage. Our encoder handles Unicode correctly, and the decoder reports errors for invalid input. No server round-trips—all processing is local. Your data never leaves your device.
How the Base64 Tool Works
- Choose Encode or Decode mode. Encode converts text to Base64; Decode converts Base64 back to text.
- Paste or type your input. For encode: any text. For decode: a valid Base64 string.
- Click the action button. The result appears instantly. Invalid Base64 shows an error when decoding.
- All processing happens in your browser. Your data never leaves your device.
Why Use This Tool?
Base64 encodes binary data as ASCII text for safe transmission. APIs use it for images in JSON. Data URIs embed images in HTML/CSS. Email attachments are Base64-encoded. This tool encodes and decodes instantly—no server, no signup. Perfect for developers, APIs, or anyone working with encoded strings. Your data stays private.
Understanding Base64
Base64 uses 64 ASCII characters (A–Z, a–z, 0–9, +, /) to represent binary data. Increases size by ~33%.
Encoding: Converts bytes to Base64. Decoding: Converts Base64 back to bytes. Invalid input fails on decode.
Common uses: embedding images in HTML/CSS, sending files in JSON APIs, encoding email attachments.
Unicode: Text is UTF-8 encoded before Base64. Our tool handles Unicode correctly for encode and decode.
When to use Base64
APIs: Encode binary data for JSON. Data URIs: Embed images in HTML/CSS. Email: Encode attachments. URLs: Safe encoding for special characters.
Base64 FAQ
Common Use Cases
- ✓Embedding images in HTML/CSS
- ✓API authentication
- ✓Data URI generation
- ✓Encoding binary for JSON