Free Base64 Encoder & Decoder - Convert Files & Text Online

Base64 is a binary-to-text encoding scheme that converts binary data (like images, files) into ASCII text using 64 characters (A-Z, a-z, 0-9, +, /). This makes binary data safe to transmit through text-only systems like email, JSON APIs, or embed in HTML/CSS. The encoded text is about 33% larger than the original binary data.

Use Base64 when you need to embed binary data in text formats (HTML/CSS data URIs, JSON APIs), send files through systems that only accept text (email protocols), or store binary data in text-based databases. It's perfect for small images, icons, fonts, and configuration data. However, for large files, regular file uploads are more efficient.

No, Base64 encoding actually increases file size by about 33% because it represents binary data using only 64 ASCII characters. It's not compression - it's conversion. If you need to reduce file size, compress first, then encode. Base64 is about compatibility and embeddability, not size reduction.

Yes, but it's best for small images (under 10KB) like icons, logos, or background patterns. Large images make your CSS file huge, slow to parse, and uncacheable separately. Base64 images can't be cached independently and increase CSS file size. Use regular image files with caching for photos and large graphics.

No! Base64 is encoding, not encryption. Anyone can decode Base64 strings instantly - there's no password or key. Don't use it to hide sensitive data. Base64 makes data text-safe for transmission, not secure. If you need security, use proper encryption (AES, RSA) before encoding to Base64.

Absolutely not! All encoding and decoding happens entirely in your browser using JavaScript. Your files are processed locally and never uploaded to our servers. The tool works completely offline once loaded, ensuring total privacy for sensitive files and documents.