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Base64 Encode Online

Convert plain text to Base64 encoding. Paste your text, get the encoded string immediately.

Base64 Encoder

Use this tool directly in your browser — no signup required.

Use Base64 Encoder

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How to Base64 Encode Online

  1. 1

    Paste or type your text

    Enter the plain text, JSON, HTML, or any string you want to encode.

  2. 2

    Encode

    Click encode. The tool converts each byte of your text into its Base64 representation using the standard alphabet (A-Z, a-z, 0-9, +, /).

  3. 3

    Copy the result

    Copy the Base64 string for use in your code, API calls, or configuration files.

What Base64 Encoding Actually Does

Base64 takes binary data (or text treated as bytes) and represents it using only 64 printable ASCII characters. The result is safe to embed in places that don't handle raw binary well — JSON strings, XML attributes, URL parameters, email bodies, and HTTP headers.

The encoding works by taking every 3 bytes of input and mapping them to 4 Base64 characters. This means the output is always about 33% larger than the input. It's not compression — it's a format conversion that trades size for compatibility.

Common uses: HTTP Basic Authentication encodes "username:password" as Base64. Data URIs embed file contents in HTML/CSS. MIME email encoding handles non-ASCII characters. JWT tokens contain Base64-encoded JSON payloads (technically Base64URL, which swaps + and / for - and _).

Frequently Asked Questions

Is Base64 encoding the same as encryption?

No. Base64 is an encoding, not encryption. Anyone can decode it instantly — there's no key or secret involved. Never use Base64 to "hide" passwords or sensitive data. It's a transport format, not a security measure.

Why does Base64 make the output longer?

Base64 uses 6 bits per character instead of 8. Three bytes (24 bits) become four Base64 characters (24 bits). So the output is always ~33% larger than the input, plus padding characters (=) at the end if needed.

What character set does this use?

Standard Base64 as defined in RFC 4648: uppercase A-Z, lowercase a-z, digits 0-9, plus (+), and slash (/). Padding uses the equals sign (=). For URL-safe encoding, + becomes - and / becomes _.