What is Base85 encoding and how is it different from Base64?

Base85, also known as Ascii85, is a more efficient encoding scheme than Base64. While Base64 uses 64 characters (A-Z, a-z, 0-9, +, /) and has 33% overhead, Base85 uses 85 printable ASCII characters (! through u, characters 33-117) and has only 25% overhead. Base85 encodes 4 bytes into 5 characters, whereas Base64 encodes 3 bytes into 4 characters, making Base85 approximately 25% more space-efficient. Base85 is commonly used in PDF files, PostScript documents, Adobe products, and other applications where compact text representation of binary data is crucial. It includes a special "z" character shortcut for four consecutive zero bytes, further improving compression for certain data types.

When should I use Base85 instead of Base64?

Use Base85 when you need the most efficient text encoding of binary data and space savings matter. Base85 is ideal for PDF file encoding, PostScript documents, Adobe products and workflows, embedding large binary data in text documents where size matters, storing binary data in databases with size constraints, and transmitting large files through text-based protocols where bandwidth is limited. Base85 produces output about 25% smaller than Base64 for the same input. However, use Base64 if you need maximum compatibility with older systems, URL-safe encoding (Base64 has URL-safe variants), or if the system you are working with specifically requires Base64. Base85 is case-sensitive and less universally supported than Base64, but more efficient.

How do I encode text to Base85?

Simply paste or type your text into the input field and the tool will automatically convert it to Base85 (Ascii85) format. The encoder handles all character types including special characters, Unicode, emojis, and multi-byte characters using UTF-8 encoding. The resulting Base85 string uses printable ASCII characters from 33 to 117 (! through u), making it safe for text-based transmission. The encoding happens instantly in your browser without any server uploads, ensuring complete privacy. You can copy the result to clipboard or download it as a text file. Base85 encoding is more compact than Base64, producing smaller output strings.

Can I encode files to Base85?

Yes! Click the "File" button to upload any file type (images, PDFs, documents, binaries). The tool will convert the entire file content to Base85 format. This is especially useful for PDF encoding (Base85 is natively used in PDF specification), PostScript files, Adobe product workflows, creating compact data URIs, sending files through JSON APIs with size constraints, and storing file data in databases where space efficiency matters. Base85 encoding increases file size by approximately 25%, so a 1 MB file becomes about 1.25 MB of Base85 text—more efficient than Base64's 33% increase. The tool handles files entirely in your browser for privacy.

What characters does Base85 use?

Base85 uses 85 printable ASCII characters: the exclamation mark (!) through lowercase u (character codes 33-117 in ASCII). This includes !, ", #, $, %, &, ', (, ), *, +, comma, -, ., /, 0-9, :, ;, , ?, @, A-Z, [, \, ], ^, _, `, a-u. Additionally, Base85 uses the special "z" character as a shorthand for four zero bytes (0x00000000), which provides extra compression when encoding data with null byte sequences. This makes Base85 case-sensitive and more compact than Base64. The output contains no spaces or control characters, making it safe for transmission through text-only systems.

Is Base85 encoding secure or a form of encryption?

No! Base85 is an encoding method, not encryption. Like Base64, it provides absolutely no security or protection. Anyone can easily decode Base85 strings back to the original data using free tools—it is a reversible transformation designed for data representation, not confidentiality. Base85 is designed for efficiency and compatibility, not security. Never use Base85 alone to hide sensitive information like passwords or API keys—it offers zero security. If you need to protect data, use proper encryption algorithms like AES-256 or RSA first, then optionally encode the encrypted result to Base85 for text-based transmission. Base85 is often used after encryption to encode encrypted binary data as compact text for transport in PDFs and PostScript.

What is the "z" character in Base85?

Base85 includes a special compression feature: when encoding encounters four consecutive zero bytes (0x00000000), it represents them with a single "z" character instead of the normal five-character encoding. This provides significant space savings for data that contains many null byte sequences, such as certain binary formats, padded data structures, or sparse matrices. When decoding, a "z" expands back to four zero bytes. This feature makes Base85 even more efficient than the standard 25% overhead for data with null bytes. However, the "z" character only appears when exactly four consecutive zero bytes are present—any other pattern uses the standard 85-character set.

Can I decode the Base85 string back to the original data?

Yes! Base85 encoding is completely reversible. Use a Base85 decoder tool to convert the Base85 string back to the original text or file. Copy the entire Base85 string and paste it into a decoder. For text, you will get the original text back. For files, you will need to specify the file extension and download the decoded file. The decoded data is byte-for-byte identical to the original. Make sure you copy the complete Base85 string without missing any characters, including any "z" characters, as even one missing character will corrupt the decoded output. Base85 encoding preserves all data perfectly, including Unicode, special characters, and binary file content.

Is my data safe when using this Base85 encoder?

Yes, completely safe! All encoding happens entirely in your browser using JavaScript. Your data never leaves your device and is not uploaded to any server. The tool processes everything locally on your computer or mobile device, ensuring complete privacy. Once you close or refresh the page, all data is immediately cleared from browser memory. This client-side approach is secure for encoding even sensitive data, though remember that Base85 encoding itself does not encrypt or protect data from anyone who intercepts the encoded string. If you need confidentiality, encrypt your data first with a proper encryption tool, then encode the encrypted result to Base85 for transmission.

What are common use cases for Base85 encoding?

Common uses include: encoding binary data in PDF files (PDF specification uses Base85/Ascii85); PostScript document encoding for efficient binary data representation; Adobe product workflows and file formats; embedding binary data in text documents where space efficiency matters; storing binary data compactly in databases as text fields; transmitting large files through text-based APIs where bandwidth is limited; encoding binary resources in single-file applications; creating compact data URIs for embedding files; and any scenario where Base64 would be used but space savings of 25% vs 33% overhead matters. Base85 is the most efficient standard text encoding for binary data and is particularly common in graphics, printing, and document workflows.

Free Base85 Encoder Online

Encode text and files to Base85 (Ascii85) format instantly. More efficient than Base64 with only 25% overhead. Perfect for PDF files, PostScript, and data encoding. 100% free, secure, and works in your browser.

EncodeDecode

Text to encode

File

Base85 encoded result

Other Base85 tools

Base85 Decoder•File to Base85•Base85 to File