CompressIt is a multi-platform desktop program that uses lossless algorithms to compress .txt files. CompressIt supports encoding/decoding canonical Huffman, and encoding finite Arithmetic and Lempel-Ziv77 algorithms.
The average compression ratio with canonical Huffman is 60-80%.
I built CompressIt to learn basic compression algorithms and familiarize using Qt. In later versions, CompressIt may also support lossy algorithms.