Check repeated order references
Locate references imported more than once across several exports, then confirm in the source system whether those repetitions represent legitimate transactions or an accidental second import.
Duplicate analyzer
Find duplicate lines, count occurrences and export a clean summary. Processing stays local in your browser.
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How does this tool work?
Before deleting repeated entries, establish which values recur and how often they appear. The duplicate analyser creates that inventory from one item per line: order references, participant identifiers, copied addresses or log messages. It displays only repeated lines, each with its total occurrence count. Your original list remains in the input field. The output is a frequency report, rather than a deduplicated replacement list or a uniqueness check across selected table columns. It helps you decide what deserves investigation before changing the source records.
Windows CRLF endings and standalone CR characters are converted to LF before the text is split. Each physical line then becomes a separate value for comparison. Completely empty lines are ignored, but a line consisting only of spaces remains a real value and may therefore appear as an invisible duplicate. There is no special header record: a repeated heading counts in exactly the same way as another input line.
Comparison is exact. Capitals, accents, tabs and spaces at either end remain significant. York, york and York followed by a space form three different groups. The analyser performs no Unicode normalisation, address correction or numerical conversion. An identifier written as 0012 is therefore separate from 12. This behaviour suits a check for identical strings; it does not find similar names, spelling mistakes or records that might represent the same person despite having different text.
Each occurrence increases a counter, after which only values appearing at least twice are retained. Results are sorted by decreasing frequency, with first appearance used to preserve order when counts tie. Every output line begins with its total, followed by × and the original value. A count of three means three occurrences in the input, leaving two excess occurrences if your aim is to retain one. When no value repeats, the output is empty; that does not mean reading failed.
How to use this tool
Provide one value on each line
Paste a single spreadsheet column or import a plain-text list. When checking identifiers, do not append a customer name or comment to the same line unless it belongs in the comparison.
Decide what differences should matter
If surrounding spaces or capitals should not distinguish entries, deliberately clean those differences before running the analysis. There is no switch for ignoring them during this operation.
Interpret counts before making changes
Run the analysis, inspect a few reported values, and copy or export the text report. Return to the original list to decide what to remove, since unique values are absent from the report.
Use cases
Review a participant list
Count repeated participant identifiers before removing entries manually. Identical registrations provide a reason to check the record rather than proof that a person should be deleted.
Find a recurring log message
Bring the most frequent identical log lines to the top. Different timestamps prevent a match, so remove them beforehand only when that is appropriate for your investigation.
Examples
Count imported order references
ORDER-205 occurs three times and is listed first. ORDER-104 occurs twice. Keeping one instance of each reference would require deleting two occurrences of the first and one of the second: three source lines altogether.
Input
ORDER-104
ORDER-205
ORDER-205
ORDER-104
ORDER-205Result
3 × ORDER-205
2 × ORDER-104Keep differently capitalised names separate
The two York lines are identical. The lowercase york is a separate, unique value, as is Bristol, so neither appears in the output. Lowercasing the input beforehand would deliberately change what qualifies as a duplicate.
Input
York
york
York
BristolResult
2 × YorkTips and best practices
- Pasting several columns usually inserts tabs, making the whole line the comparison value. Isolate the relevant column first or use CSV deduplication when you need to select a table key.
- Do not import the frequency report straight back into your source application: the count prefix is part of the exported text. Treat it as a checklist of values that need attention.
- Importing a CSV file does not activate CSV parsing here. A quoted field spanning several lines will be split into physical lines; use a CSV-aware tool when that distinction matters.
Frequently asked questions
Is the displayed count the number of entries to delete?
It counts every occurrence, including the first. For a result starting 4 ×, retaining one instance means removing three occurrences. The analyser does not delete any input entries automatically.
Why can apparently identical addresses remain separate?
Different capitals, trailing spaces, tabs or Unicode representations are sufficient to distinguish them. The analyser compares the characters it receives; it does not test address deliverability or establish that two addresses belong to the same person.
Can I choose a key column from a CSV file?
No. This analyser does not interpret CSV columns or quoted records. CSV deduplication lets you select the columns that define a repetition; the analyser here counts complete text lines.
What does an empty analysis result mean?
No non-empty line occurs at least twice with exactly the same spelling. It does not establish business-level uniqueness: differently written names may refer to the same entity while remaining different strings.
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