How it works
Parse comma-separated CSV, preserve its first header row, and keep the first exact case-sensitive instance of each subsequent row.
Input definitions
- CSV with header
- Plain text; maximum 200,000 characters.
A worked example
- CSV with header
- name,city Ada,London Ada,London Lin,Paris
Assumptions & limits
Comma delimiter, header first, 2,000 rows including header. Blank lines ignored, quoted cells supported. Formula escaping may alter dangerous cell prefixes.
Sources & review
Maintained by AnsRio. Methods and examples use automated checks; this does not imply independent professional certification.
Method updated 2026-10-17. Content checked against the stated method and examples. Our verification approach.
Common questions
Are duplicate CSV rows compared case sensitively?
Yes. Every parsed cell must match exactly, including case and whitespace. The header is retained separately, and the first occurrence of each data row is kept.
Does this tool execute the code or data I paste?
Inputs are treated as data under the stated parser or transformation. Output is displayed as text. Parsing or formatting does not establish that the content is safe to execute elsewhere.
How does the Remove duplicate CSV rows tool work?
Parse comma-separated CSV, preserve its first header row, and keep the first exact case-sensitive instance of each subsequent row.
What are the assumptions and limits of Remove duplicate CSV rows?
Comma delimiter, header first, 2,000 rows including header. Blank lines ignored, quoted cells supported. Formula escaping may alter dangerous cell prefixes.