Base64 Encoder, Decoder & File Converter

Encode plain text, UTF-8 strings, and files to Base64 format, or decode Base64 data back to readable text and images.

URL-Safe Base64 (`-` and `_` instead of `+` and `/`)

PLAIN TEXT INPUT

OUTPUT

Free Online Base64 Encoder, Decoder & Image Data URL Generator

Base64 is a binary-to-text encoding scheme defined in RFC 4648 that represents binary data using a set of 64 printable ASCII characters (`A-Z`, `a-z`, `0-9`, `+`, `/`). Base64 is widely used across modern web development, email transport protocols (MIME), REST API payloads, and CSS/HTML inline assets to embed binary data into text files. Our Free Online Base64 Converter lets you encode text, decode strings, and convert image files to inline Data URLs.

Equipped with UTF-8 international character support, URL-safe encoding mode (substituting `+` and `/` with `-` and `_`), and instant image file drag-and-drop preview, our tool operates 100% locally in your web browser using FileReader and TextEncoder APIs. Your uploaded files and private text never leave your machine.

How to Encode & Decode Base64 Strings & Files

Choose Conversion Mode: Select between "Encode Text", "Decode Text", or "File / Image to Base64 Data URL".
Input Data or Upload File: Type plain text into the input box or drop image/pdf files into the file uploader.
Toggle URL-Safe Mode: Enable "URL-Safe Mode" if your Base64 string will be passed inside web URL query parameters or HTTP header tokens.
Copy Output: Instantly copy your Base64 string or inline HTML `data:image/png;base64,...` code with 1 click.

Key Features & Technical Capabilities

Image to Base64 Data URL Generator: Convert JPG, PNG, WebP, SVG, and GIF images into inline CSS/HTML `data:image/...` strings.
URL-Safe Base64 Encoding (RFC 4648 §5): Automatically replaces `+` with `-` and `/` with `_`, stripping trailing `=` padding for clean URL parameters.
Full UTF-8 Unicode Support: Encodes complex emojis, Asian characters, and special symbols without double-byte corruption.
100% Client-Side Browser Privacy: Documents, images, and confidential API keys are converted locally in memory without uploading.

Best Practices for Base64 Encoding

Base64 is NOT Encryption: Base64 is a data representation format, NOT security encryption. Anyone can decode Base64 back to raw text. Never rely on Base64 to hide secret passwords or API tokens.
Inline Small Images Only: Inlining small icons (< 10 KB) as Base64 Data URLs reduces HTTP request count. Avoid Base64 encoding large photos, as Base64 increases raw file size by ~33%.
Use URL-Safe Base64 in Query Strings: Standard Base64 uses `+` and `/` which get mangled by web server URL parsers. Always use URL-safe mode for URL parameters.

Frequently Asked Questions (FAQ)

Is Base64 an encryption algorithm?

No! Base64 is an encoding scheme, not encryption. Base64 can be decoded instantly by anyone without a secret key.

Why does Base64 increase file size by 33%?

Base64 converts 3 bytes of binary data (24 bits) into 4 ASCII characters (32 bits), resulting in a 33.3% file size inflation.

What is a Base64 Data URL?

A Data URL (e.g. data:image/png;base64,...) allows web developers to embed images directly inside HTML <img> tags or CSS background-image styles without separate HTTP requests.

Are my uploaded image files sent to any server?

No! File conversion executes 100% locally in your web browser using HTML5 FileReader API.