Compress text using neural arithmetic coding (NC05 format).
Upload any file (up to 1 MB) to compress.
The format is auto-detected: text files use neural compression (NC05), binary files use hybrid compression (NC06) where text-like regions are neural-compressed and binary regions are gzip/lzma-compressed.
Upload a .nc file to decompress, or paste base64 data from the Compress Text tab.
Supports both NC05 (text) and NC06 (binary) formats.
Or paste base64 data:
How it works: A 135M-parameter language model predicts the next token at each step. Those predictions feed an arithmetic coder -- high-confidence predictions cost nearly zero bits. The same model runs on both sides, guaranteeing perfect lossless reconstruction.
Text (NC05): Text is tokenized and neural-compressed directly. Achieves ~15% ratio on English text (2.5x better than gzip).
Binary (NC06): Files are segmented into text-like and binary regions. Text regions are neural-compressed;
binary regions are compressed with gzip or lzma. The hybrid approach beats gzip on files with significant text content.
Apache 2.0 | Made by Roberto Tacconelli | arxiv.org/abs/2602.19626 | tacconelli.rob@gmail.com | roberto@elizetaplus.com