CSV Merger
Merge multiple CSVs into one.
Stack CSVs together
Paste several CSVs and this combines their rows into one file, aligning on the shared header so columns stay in order. It is the quick way to consolidate monthly exports into a single sheet.
It is the routine consolidation task — stitching twelve monthly exports into one annual sheet, or combining regional files — done in seconds without a spreadsheet formula.
Match your headers
Files should share the same columns for a clean merge. Everything runs in your browser, so the combined data never leaves your device. Your files are combined on your device and never uploaded.
Frequently asked questions
What does this csv merger do?
Merge several CSV blocks into one combined output without uploading your data.
How do I separate the CSV files?
Paste each CSV block with a blank line between them. Each block is parsed on its own, then the rows are combined in order.
What does "keep one header" do?
It drops the first row of every block after the first, so repeated header rows do not end up in the middle of your data. Untick it if your blocks have no headers.
Does it match columns by header name?
No. Rows are stacked as they are, so every block needs the same columns in the same order. Reorder mismatched files first.
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