Find the Cdr of a List

This tool extracts the tail of a list known as the “cdr” in Lisp-style list processing. You can remove the first item or repeatedly remove leading items to simulate cdr, cddr, cdddr, etc. Options include trimming whitespace, skipping empty lines, and outputting multiple CDR levels in a sequence. Everything runs instantly in the browser.

Paste your input above or import a file below.
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Supported file types: .txt, .csv, .tsv, .log, .json, .xml, .md, .ini, .yaml, .yml, .html, .htm, .css
Total items: 0
Options
Trim lines
Ignore empty lines
Output multiple CDR levels

How to Use:

  1. Paste or import your list into the Input List box.
  2. Adjust the Options:
    • Trim lines: removes leading/trailing whitespace
    • Ignore empty lines: skips blank rows
    • Output multiple CDR levels: shows each step of cdr removal
  3. The result appears instantly in the CDR Output box.
  4. Click Copy Output or Export to File as needed.
  5. Use Clear All to reset the tool completely.

Example:

Input:

apple
banana
cherry
date
elderberry

With multi-CDR enabled:

banana
cherry
date
elderberry

cherry
date
elderberry

date
elderberry

elderberry

Without multi-CDR:

banana
cherry
date
elderberry

Common Use Cases:

Use this tool to simulate list tail evaluation, drop headers from datasets, or recursively strip the first element from structured text input. It’s ideal for list-processing, educational tools, or data manipulation tasks requiring a recursive tail extraction.

Useful Tools & Suggestions:

If you’re finding the cdr of a list (everything except the first item), Shift List Items can give you similar control when adjusting position or skipping elements. And if you’re doing this repeatedly or as part of a larger workflow, Slice a List helps you fine-tune which portion to keep. It’s a practical approach when you’re working with recursive logic, tail operations, or functional-style list processing.

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