Base64 Encoder / Decoder
Instantly encode or decode Base64 text, right in your browser.
Enter text below to instantly encode or decode it as Base64 - entirely in your browser, nothing is sent to our servers.
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What Is Base64?
Base64 turns any data into text using only letters, digits, + and /. It is used to send binary data through text-only channels such as JSON, email or HTTP headers. This tool encodes and decodes text in your browser.
When to Use It
- To decode a Base64 value found in a config file, token or API response.
- To create a Basic Authorization header value.
How to Use It
- Paste the text or Base64 string.
- Choose encode or decode.
Understanding the Result
Base64 output is about 33% larger than the input. Trailing = signs are padding. URL-safe Base64 uses - and _ instead of + and /.
Limitations
Base64 is encoding, not encryption - anyone can decode it, so never use it to protect secrets. For images use Image to Base64.
Examples
| Text | Base64 |
|---|---|
Hello | SGVsbG8= |
user:pass | dXNlcjpwYXNz |
Byteary | Qnl0ZWFyeQ== |
The user:pass value is exactly what goes into an HTTP Basic auth header: Authorization: Basic dXNlcjpwYXNz.
Where You Will See Base64
- JWTs - each part is Base64URL-encoded JSON. Decode them with the JWT Decoder.
- Data URIs - small images embedded in CSS or HTML. See Image to Base64.
- Email attachments (MIME) and Kubernetes Secrets, which store values in Base64.
- API keys and certificates in PEM files.
Common Problems
- Garbled output: the original data was binary (an image or a file), not text.
- "Invalid character": the string is URL-safe Base64 (with
-and_) or has line breaks in it. - Accents and emoji broken: text must be encoded as UTF-8 first, which this tool does.
Read our full guide: what is Base64 encoding.
Frequently Asked Questions
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