What is Base64?
Base64 encoding converts binary or text data into a string of printable ASCII characters, making it safe to transmit through systems designed only for text. It is reversible — decoding returns the exact original data — and is one of the most widely used encoding formats on the web.
How to Use This Base64 Encoder
- Paste your text into the Input box above.
- Click Encode to convert it to Base64, or Decode to convert a Base64 string back to plain text.
- Copy your result with the Copy Output button.
When Do You Need Base64?
Base64 is used whenever binary or special-character data needs to travel through a text-only channel. Common cases include embedding small images directly inside HTML or CSS using data URIs, attaching files in email via MIME, encoding credentials in HTTP Basic Authentication headers, and storing binary blobs inside JSON payloads or URL parameters where raw binary isn't safe to transmit.
Frequently Asked Questions
What is Base64?
Base64 is a binary-to-text encoding scheme that represents binary data using 64 printable ASCII characters (A-Z, a-z, 0-9, +, /). It is used to safely transmit data through systems that only support text.
When is Base64 used?
Base64 is commonly used to embed images directly in HTML or CSS, attach binary files in email (MIME), encode authentication credentials in HTTP headers, and pass binary data through JSON or URL query strings.
Is Base64 encryption?
No. Base64 is encoding, not encryption. It does not provide any security or confidentiality — anyone can decode a Base64 string back to its original form instantly, with no key required.
What is the size overhead of Base64?
Base64 encoding increases data size by approximately 33%, since every 3 bytes of input become 4 characters of output. This overhead is the trade-off for safe text-based transmission.