Enumerate Integers

The Enumerate Integers tool takes a list of integers and adds a line number (or index) in front of each one. You can customize where the numbering starts, choose your delimiter, and control how invalid entries are handled. It updates instantly as you type or import data.

Whether you’re creating labeled datasets, prepping structured logs, or building numbered sequences for forms or training materials this tool gives you fast, consistent output.

Paste your input above or import a file below.
No file chosen
Supported file types: .txt, .csv, .tsv, .log, .json, .xml, .md, .ini, .yaml, .yml, .html, .htm, .css
Total enumerated: 0
Options


Ignore non-integers
Maximize output

How to Use:

  • Paste one integer per line into the Input Integers box
  • Or click Choose File to import a .txt, .csv, or other plain-text file
  • Set the Start at number to define the starting index for enumeration
  • Choose a Delimiter to insert between the index and value (e.g., :, ), -)
  • Toggle Ignore non-integers to skip or include lines that aren’t valid integers
  • Toggle Maximize output to expand the output display area
  • Click Enumerate or type/edit to see results update in real time
  • Use Copy Output or Export to File to save the result
  • Click Clear All to reset the tool and start over

What Enumerate Integers can do:

This tool adds line numbers to integers in a clean, structured format. You define the numbering and delimiter, and it handles everything else including invalid inputs if needed. It supports large input lists and returns simple, well-formatted output.

Example:

Input:

15
20
invalid
25

Start at: 1 Delimiter: : Ignore non-integers: On

Output:

1: 15
2: 20
3: 25

Common Use Cases:

Use it to number test data, identify rows in logs, prepare student answer keys, build training datasets, or inject structure into otherwise flat lists. It’s a lightweight way to give data useful labels.

Useful Tools & Suggestions:

If you’re using Enumerate Integers to add structure, try Join Integers to combine the output into a single line for compact display. Or pair it with Print Integer Information if you want to add more detail to each item in your list.

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