Free Base64 Encode & Decode - Convert Text and Images Online

A Base64 is a binary-to-text encoding scheme that converts binary data into a string of printable ASCII characters. It is commonly used to embed images in HTML/CSS, transmit data in URLs, and encode email attachments.

A No. Base64 is an encoding method, not encryption. It does not provide any security — anyone can decode a Base64 string. Never use Base64 to protect sensitive data like passwords.

A Base64 encoding increases data size by approximately 33%. This is because it represents every 3 bytes of binary data as 4 ASCII characters. The trade-off is universal compatibility with text-based protocols.

A Yes! Use a data URI like: <img src=data:image/png;base64,... />. This eliminates an HTTP request but increases HTML file size. Best for small icons and logos under 10KB.

A This tool supports JPG, PNG, GIF, WebP and SVG images. Simply upload your image file and the Base64 data URI will be generated automatically.

A To convert a Base64 string back into a file, paste your Base64 encoded data into the decoder input area. If the original data was a PDF, MP3, or any other file type, the tool will automatically detect the file's binary structure upon decoding. Once decoded, a download link will appear, allowing you to save the original file to your device, preserving its format and content.

A If you paste an invalid Base64 string into our decoder, the tool will typically display an error message, indicating that the input is not a valid Base64 format. This could be due to incorrect characters, padding issues, or malformed data. The decoder needs a properly structured Base64 string to successfully convert it back to its original text or file format. Always double-check your input for integrity.

A Yes, this Base64 encoder handles all types of text, including special characters, emojis, and characters from non-English alphabets (Unicode). Before encoding, text is typically converted to its UTF-8 byte representation, which Base64 then processes. Simply paste your text, regardless of its character set, into the input field. The tool will accurately convert it to a Base64 string, ensuring proper data integrity for web transmission or storage.

A Base64 encoding is excellent for embedding small icons, logos, or images (typically under 10KB) directly within HTML email newsletters. Using data URIs (`<img src="data:image/png;base64,...">`) bypasses external image requests, which can improve loading times and reduce issues with image blocking by email clients. Simply encode your image using our tool, then paste the resulting data URI into your newsletter's HTML code for reliable display.

A While our free online Base64 encoder handles most common image and document sizes efficiently, very large files (e.g., several hundred MBs or GBs) might exceed browser or server processing limits. For optimal performance and to prevent timeouts, we recommend keeping file sizes under 50MB. For extremely large files, consider using local command-line tools for encoding.