How can you remove duplicate CSV rows without an upload?
Short answer
Parse the CSV as records, compare the complete row values, and retain the first occurrence of each distinct row. Sheet Reserve’s browser tool does this locally and can optionally ignore letter case. Rows sharing one ID but differing in another column remain distinct. Trim unintended surrounding spaces first only if those spaces should not affect equality.
For 001,Ada, 001,Ada, and 001,ada, exact comparison retains two rows. Case-insensitive comparison retains one, keeping the first spelling.
Why is duplicate-row removal different from duplicate-key repair?
Two customer records with the same ID and different addresses require a source-specific rule. Full-row deduplication keeps both; it does not choose an authoritative address or merge records.