Base64 Encode/Decode
Encode text to Base64 or decode Base64 to text
How to base64 encode/decode online
Encode text to Base64 or decode Base64 strings back to plain text.
- Paste or type your plain text into the input area to encode it, or paste a Base64 string to decode it.
- Click "Encode" to convert your text into a Base64-encoded string.
- Alternatively, click "Decode" to convert a Base64 string back into readable text.
- Review the output in the result area below.
- Click "Copy" to copy the encoded or decoded result to your clipboard.
About Base64 Encode/Decode
Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A-Z, a-z, 0-9, +, and /). It was originally designed to safely transmit binary data over channels that only support text, such as email (MIME encoding) and certain API protocols. Today, developers use Base64 encoding in a wide range of scenarios: embedding small images directly in HTML or CSS as data URIs, passing binary data in JSON payloads, encoding authentication credentials in HTTP Basic Auth headers, and storing binary blobs in text-based configuration files.
Common use cases you might encounter include converting an image to a data URI for inline embedding (data:image/png;base64,...), encoding API keys or tokens for transport in URL parameters, and decoding Base64 strings received from APIs or webhook payloads. Base64 is also used internally by JWT (JSON Web Tokens) — if you have ever needed to inspect the payload of a JWT, you are decoding Base64.
This tool fully supports UTF-8 text, including accented characters, CJK (Chinese, Japanese, Korean) text, and emoji. The encoder first converts your input to UTF-8 bytes, then encodes those bytes as Base64. The decoder reverses the process, correctly reconstructing multi-byte characters. All processing runs locally in your browser — your data is never sent to any server, making this safe to use with passwords, API keys, and other sensitive strings.
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Frequently Asked Questions
What is Base64 encoding?
Base64 is a way to represent binary data using only printable ASCII characters. It is commonly used in email, data URLs, and APIs where binary data must be embedded in text.
Does this support Unicode and emoji?
Yes. The encoder handles UTF-8 text including accented characters, CJK text, and emoji by converting to UTF-8 bytes before Base64 encoding.
Why is the Base64 output longer than the input?
Base64 encoding increases size by about 33% because it represents every 3 bytes of input as 4 ASCII characters. This is the expected trade-off for text-safe encoding.
Is my data sent anywhere?
No. All encoding and decoding happens entirely in your browser. Your data never leaves your device.