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Merge & deduplicate
Combine CSV or XLSX files, align headers, and remove duplicates.
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Files are stored locally and deleted automatically after 6 hours.
0 files ready · 0 merged rows
Merged preview
Aligned headers and sample rows.
How to merge CSV/XLSX with fewer data errors
Merge mode aligns headers across files and can remove duplicate rows. Use it to consolidate multiple extracts into one normalized dataset.
Recommended workflow
- - Upload all source files and inspect the merged preview headers.
- - Enable deduplication when sources overlap across time periods.
- - Use column-key deduplication when one business key identifies unique records.
- - Export both CSV and XLSX if different stakeholders use different tools.
Quality checks before delivery
- - Validate the selected dedup key is stable and not blank.
- - Compare total input rows versus unique output rows for reasonableness.
- - Spot-check a few critical records that appear in multiple files.
Common mistakes
- - Deduplicating by full row when only a business key should be unique.
- - Merging files with different semantic meanings under the same header name.
- - Ignoring blank-key rows when deduplicating by selected column.
FAQ
When should I deduplicate by column?
Use column mode when one ID (email, order_id, sku) defines uniqueness.
Why do I see fewer rows after merge?
If deduplication is enabled, repeated records are intentionally removed.