What is Base64 encoding?

Base64 converts binary data into a 64-character ASCII alphabet (A-Z, a-z, 0-9, +, /) so binary data can be safely transmitted over text-based protocols like email or HTTP headers. Every 3 bytes of binary data becomes 4 Base64 characters.

Why does Base64 encoded data end with "=="?

Base64 encodes data in 3-byte groups. If the input length isn't divisible by 3, padding characters (=) are added to make the output length a multiple of 4. One = means 2 bytes remain; == means 1 byte remains.

Is Base64 the same as encryption?

No! Base64 is encoding, not encryption. Anyone can decode a Base64 string. Do NOT use Base64 to hide sensitive data — use proper encryption like AES or RSA instead.

How do I embed a Base64 image in HTML?

Use this format: . Replace {BASE64_STRING} with your encoded image data and change "image/png" to the correct MIME type.

What is URL-safe Base64?

Standard Base64 uses + and / which have special meanings in URLs. URL-safe Base64 replaces + with - and / with _, making it safe for use in URLs and filenames without percent-encoding.

Base64 Encode & Decode - Free Online Base64 Converter

How to Use Base64 Encode & Decode

1
Select "Encode" or "Decode" mode using the toggle.
2
For encoding: paste your text or upload a file.
3
For decoding: paste your Base64 string.
4
The result appears instantly below.
5
Click "Copy" to copy the output, or "Download" for file results.

About Base64 Encode & Decode

Base64 is a binary-to-text encoding scheme that represents binary data using only printable ASCII characters. Our Base64 tool handles both encoding (text/file → Base64) and decoding (Base64 → text) in a clean, simple interface.

Base64 encoding is used widely in web development: embedding images directly in HTML/CSS, encoding binary data for JSON APIs, email attachments (MIME), HTTP Basic Authentication headers, and storing binary data in text-based formats like XML or JSON. Developers regularly need to encode and decode Base64 strings when debugging APIs or building integrations.

The tool also handles file encoding — upload any file (image, PDF, document) and get its Base64 representation, ready to embed in HTML img tags, CSS background URLs, or JSON payloads. The encoded string is shown with the appropriate data URI prefix for direct use.

Base64 Encode & Decode