How much does Base64 increase data size?

Base64 encoding increases data size by approximately 33% because 3 bytes of binary data are represented as 4 characters.

Updated: August 2026 • Verified v1.2

Base64 Encoder (Text & Files)

Q: Does this support UTF-8 special characters and emojis?

Yes! Unlike naive btoa implementations that fail on non-ASCII characters, our encoder properly handles full multi-byte UTF-8 character sets and emojis.

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Convert plain text, UTF-8 strings, images, and files into standard Base64 or Data URI format.

Local Browser Execution: Your input is processed locally in your browser and is not sent to UTL servers.

RFC 4648 Base64 Encoding: 3 Binary Bytes (24 bits) -> 4 Base64 ASCII Chars (24 bits)

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Understanding Your Results

Translates 8-bit binary bytes into 6-bit Base64 character sequences (A-Z, a-z, 0-9, +, /). Data size increases by exactly 33.3% due to the 3-to-4 byte expansion.

Practical Guidance & Next Steps

Use Data URI format (`data:image/png;base64,...`) when inlining small icons (< 5KB) directly into HTML or CSS to eliminate extra HTTP requests.

What is this?

A versatile encoding tool that translates ASCII/UTF-8 text, binary files, and images into standard Base64 representation (RFC 4648).

How does it work?

1. Type or paste text, or drag-and-drop any file/image. 2. Choose between raw Base64 string or full `data:image/...;base64,...` Data URI. 3. Copy the encoded string with one click.

Why use it?

Ideal for embedding small icons into CSS/HTML files, transmitting binary data through text-only API protocols, and constructing Basic Auth headers.

Technical Scope & Calculation Limitations

Base64 is an encoding format, NOT encryption. Encoded data is easily reversible and provides zero cryptographic confidentiality on its own.

Frequently Asked Questions

Yes! Unlike naive btoa implementations that fail on non-ASCII characters, our encoder properly handles full multi-byte UTF-8 character sets and emojis.

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