Base64 Encoder
A Base64 Encoder converts binary data or text strings into a Base64 representation using a set of 64 printable ASCII characters. It is used to safely transmit binary data over text-based protocols like HTTP, email (MIME), and JSON.
What is Base64 Encoder?
Base64 encoding groups every 3 bytes of input into 4 printable ASCII characters drawn from A-Z, a-z, 0-9, + and /. Padding characters (=) are appended to make the output length a multiple of 4. The encoded output is approximately 33% larger than the original input but is safe to embed in URLs, JSON strings, HTTP headers, and email bodies. This tool runs the encoding using the browser's built-in atob/btoa or TextEncoder APIs.
Use Cases
- Embedding images inline in HTML using data URIs.
- Encoding binary attachments in email (MIME).
- Transmitting binary data in JSON API payloads.
- Storing binary blobs in text-based storage systems.
How to Use It
Type or paste your text into the input field.
The Base64 encoded output appears instantly.
Click Copy to transfer the encoded string to your clipboard.
Pros
- Produces pure ASCII output safe in any text context.
- Instant, offline, private encoding.
Limitations
- Encoded output is 33% larger than input.
- Not a form of encryption or security.
Best Practices
- Use URL-safe Base64 (replace + with - and / with _) for URL parameters.
- Remember that Base64 is encoding, not encryption—it does not hide data.
Common Mistakes to Avoid
- Confusing Base64 encoding with encryption—Base64 is reversible and not secure.
- Using standard Base64 in URLs without URL-encoding the + and = characters.
FAQs
Is Base64 safe for passwords?
No. Base64 is not encryption. It is trivially reversible. Never use it to hide sensitive data.
What is URL-safe Base64?
A variant that replaces + with - and / with _ to make the encoded string safe in URL parameters without percent-encoding.