Drag Unix commands into a pipeline, configure them, and watch your text transform stage by stage.
Unix pipelines — chaining commands with the pipe operator | — are one of the most powerful concepts in computing. Yet most people learn them by reading documentation or trial-and-error at the terminal. Pipe Lab was built to make pipeline construction visual and incremental: you can see exactly what each stage does to the data, building up from a single command to a complex multi-stage pipeline.
Pipe Lab is an interactive Unix pipeline builder. You start with input text, drag Unix commands into a pipeline, configure each command's parameters, then run the pipeline to see how the data transforms step by step through every stage. It simulates common shell commands including grep, sort, uniq, wc, head, tail, cut, tr, sed, awk, nl, rev, fold, and uniq.
Each command is implemented as a JavaScript function that takes an array of text lines and returns a transformed array. When you run the pipeline, the output of one stage becomes the input of the next — exactly like a real Unix pipe. The step-by-step output shows the intermediate result after each command, with lines added or removed highlighted so you can see exactly what changed.
Take it further: