Remove Duplicate Rows: Deduplicate Tables
Customer lists from several sources repeat people and raise messaging costs. This tool finds repeats in CSV, TSV, XLSX or JSON in your browser. Pick Email or Phone as the key. UTF-8 and correct delimiters required.
Step by step
- Save the list as UTF-8, check the delimiter.
- Open the tool, upload, confirm headers.
- Mark key columns like Email.
- Run dedup, review duplicate counts.
- Download the clean list.
Example scenario
A 5000-row list keyed on Email finds 620 repeats, dropping to 4380 unique records. The clean list uploads to mailing with no double sends.
Check your result
Filter the key column for leftover repeats. Removed plus remaining must equal the original count. Too many removed means too broad a key.
Frequently asked questions
Which columns as keys?
The truly identifying field; Email usually suffices.
Empty cells counted?
They can be; clean empties first.
Case and spacing?
They matter; lowercase and trim first.
Formatting kept?
No, values only.
Open the tool: Remove duplicate rows →
Keep an original copy before processing your file. Examples are illustrative; results depend on your document.