Free Base64 Encoder & Decoder Online

Developer Tools

What is Free Base64 Encoder & Decoder Online?

Base64 Encoder is a browser-based utility that converts text and binary data into a Base64 string — a representation using 64 ASCII characters (A-Z, a-z, 0-9, +, /). It's the standard way to embed binary data like images in HTML, encode credentials in HTTP headers, or safely transmit binary data over text-based protocols like JSON or email. Base64 is everywhere in web development: API tokens, email attachments, and data URIs all use it.

How it works

The encoder uses JavaScript's TextEncoder API to handle any UTF-8 input, then converts each 3-byte sequence into 4 Base64 characters. Padding (=) is added if the input length isn't divisible by 3. URL-safe mode replaces + and / with - and _ to avoid issues in URLs.

Features & Benefits

Runs entirely in your browser - no server, no upload
Supports full UTF-8 including emojis and international characters
Handles both standard Base64 and URL-safe Base64 (using - and _ instead of + and /)
Shows clear error messages for invalid Base64 input

Frequently Asked Questions

What is Base64 encoding?

Base64 converts binary data (or text) into a set of 64 printable ASCII characters. It's commonly used to embed images in HTML, send data in URLs, or store binary data as text.

Is my data safe?

Yes. Encoding and decoding happens entirely in your browser with no server involvement.

Does it support emojis?

Yes. This tool uses TextEncoder internally, so any UTF-8 text including emojis, CJK characters, and accented letters works correctly.

What's the difference between standard and URL-safe Base64?

Standard Base64 uses + and / characters which are special in URLs. URL-safe Base64 replaces them with - and _ so the result can be used directly in URLs without encoding.

Related Tools

URL Encoder & Decoder

Encode and decode URL components instantly in your browser. Percent-encodes special characters. No data sent to servers.

JSON Formatter & Validator

Format, validate, and minify JSON instantly in your browser. Your data never leaves your device.

JWT Decoder

Decode JWT tokens and inspect header and payload instantly in your browser. Your tokens never leave your device.

Popular Utilities

JSON Formatter & Validator

Format, validate, and minify JSON instantly in your browser. Your data never leaves your device.

JWT Decoder

Decode JWT tokens and inspect header and payload instantly in your browser. Your tokens never leave your device.

Word Counter

Count words, characters, sentences, and estimate reading time instantly in your browser. No sign-up required.