Highlight duplicate rows in Excel
Upload your sheet and download it with the repeated rows shaded in colour and numbered by group. No row is deleted: they are only marked for review.
What it is for
Sometimes a duplicate isn't an error to delete unseen: it may be legitimate data, or something worth reviewing before you decide. This tool is the careful step for those cases. It deletes nothing: it returns your whole sheet, with the repeated rows shaded in colour and numbered by group, so you can see them, review them and decide for yourself.
It is the opposite of removing duplicates, which deletes straight away. Here you look first; deleting comes later, if you want it.
What you get back
The result is an .xlsx with all your rows intact and two marks on the ones
that are repeated:
- Background colour on each duplicate row, to spot them at a glance as you scroll through the sheet.
- A "Grupo" column with a number: every row that is the same as another shares the same group number. So you know not only that a row is repeated, but which other one it matches.
The group column is also the backup that survives if you later export to CSV, where the background colour is lost. You can turn it off if you prefer just the shading.
What defines a duplicate
By default the whole row is compared: two rows match only if every column is
identical. If your criterion is narrower — the same email even when the rest
differs — name the deciding columns under "columns to compare", by name, Excel
letter (A, B, AA) or number.
As in the other tools, ignore spaces at the start and end is on (stray spaces are the number one reason duplicates go undetected) and match upper and lower case is off. If you only care about the repeats, turn on "keep only duplicates" and the unique rows are left out of the result.
Highlight or remove: which to use
- Use highlight when you want to see and review the duplicates without losing any row: when the repeat might be legitimate or when you need to understand why it duplicated before touching anything.
- Use remove duplicate rows when you already know they are surplus and want the clean file straight away, with a single copy of each row.
A common sequence is to highlight first to inspect, then remove afterwards, confident about exactly what will go.
Frequently asked questions
Is any row deleted?
No, none. That is the whole point: this tool only marks. If you want them removed, that is remove duplicate rows.
What is the group number for?
To tell which rows are the same as each other. Two rows with group number 3 are
duplicates of one another. Sort or filter by that column and every repeat of each
value sits together.
Why does my file come back as .xlsx when I uploaded a CSV?
Because colour shading only exists in .xlsx. A CSV or a legacy .xls is
delivered as .xlsx to preserve the highlight. The group column would survive a
later export to CSV.
Does a row with an extra space count as a duplicate?
With "ignore spaces" on — the default — yes. "Ana García" and "Ana García "
are marked as the same group. That is exactly the case Excel does not solve on
its own.
Can I keep only the repeated rows?
Yes. Turn on "keep only duplicates" and the result will include only the rows that have at least one repeat, already shaded and numbered by group.