Repeating List Item Finder

Scans a separator-delimited list and reports every distinct value that appears more than once, each shown exactly one time alongside its total occurrence count, e.g. "apple (×3)". A free online tool from Staaarter, right in your browser.

Runs locallyUpdated 2026-07-27

Overview

Introduction

When you're cleaning up a pasted list, knowing which values repeat, and how many times, is often more useful than seeing every single duplicate line individually.

This tool collapses each repeated value down to one summary line with its total count, giving you a quick census of what's duplicated in your list.

What Is Repeating List Item Finder?

A frequency-based repeat detector: it counts every distinct value in your list and keeps only the ones that occur two or more times.

Each qualifying value appears exactly once in the output, annotated with how many times it occurred in the input, e.g. "apple (×3)".

How Repeating List Item Finder Works

The input is split into items using the selected separator, then counted with a running tally keyed by each distinct value.

Values with a tally of two or more are kept, formatted as "value (×count)", and listed in the order they first appeared.

When To Use Repeating List Item Finder

Use it to get a quick summary of which values are duplicated in a pasted list without manually eyeballing hundreds of lines.

It pairs well with Repeating List Item Remover once you've confirmed which values need de-duplicating.

Features

Advantages

  • Gives a compact, one-line-per-value summary instead of a long list of raw duplicates.
  • Shows exact occurrence counts, useful for spotting outliers or data-entry mistakes.

Limitations

  • Doesn't show the position of each occurrence; use List Item Finder if you need that.
  • Comparison is exact and case-sensitive; "Apple" and "apple" are treated as different values.

Examples

A list with one repeating value

Input

apple
banana
apple
apple
cherry

Output

apple (×3)

"apple" appears three times total and is reported once with its count; "banana" and "cherry" each appear once and are excluded.

Multiple repeating values, comma-separated

Input

a,b,a,c,c (comma separator)

Output

a (×2)
c (×2)

Both "a" and "c" repeat twice each; "b" appears once and is left out.

Best Practices & Notes

Best Practices

  • Run this before Repeating List Item Remover to preview exactly which values will be affected by de-duplication.
  • Use Popular List Item Finder instead if you want every value's count, not just the repeated ones.

Developer Notes

Frequency counting uses a `Map<string, number>` keyed by the raw item string, incremented via `counts.get(item) ?? 0`, which preserves first-insertion order when iterated for output.

Repeating List Item Finder Use Cases

  • Spotting accidental duplicate entries in a pasted spreadsheet column
  • Checking how many times a specific tag or ID recurs across a dataset
  • Previewing what a de-duplication pass will collapse before running it

Common Mistakes

  • Expecting this tool to list every occurrence individually; it deliberately collapses repeats into one summary line per value.
  • Assuming whitespace-padded duplicates like "apple" and "apple " will be merged; they're compared exactly as split, with no trimming.

Tips

  • If a value you expect to repeat doesn't show up, check for stray trailing whitespace or inconsistent casing in your source data.
  • Combine with a custom separator if your list isn't newline- or comma-delimited.

References

Frequently Asked Questions