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CSV Merge & Join

Combine two CSV datasets using a matching column. Ideal for enriching exports with metadata, syncing CRM lists, or joining analytics tables.

Free to use, no watermarks, runs in your browser—nothing uploads to our servers

CSV data

Supports header rows, quoted values, and multi-line fields.

Secondary CSV data (to join)

Delimiter

Use first row as headers

Report a bug

If this tool misbehaves, share a quick summary so we can investigate. We include the tool URL automatically—no need to copy and paste.