Merge multiple CSV files into one. Stack rows vertically (append) or join horizontally by a shared key column. Download the unified dataset.
Open CSV Merger → free, no sign-inCombining multiple CSV files into one shouldn't require a script. CSV Merger handles two common cases: stacking files vertically (appending rows from multiple exports into one dataset) or joining them horizontally (merging columns from different sources based on a shared key column). Upload the files, pick the merge strategy, download the result.
Data analysts combining monthly exports into a full-year dataset, developers merging data from multiple API responses, anyone consolidating data from several files into one for analysis or import.
No tutorials. No learning curve. Open it and get started.
No server uploads. Supports both append (row stacking) and join (column merging) in the same tool — two different operations, one place.
Completely free. No trial period. No premium tier for basic functionality. No account required. Use it as often as you need.
One job, done well. CSV Merger was built to solve a specific problem cleanly. No feature bloat, no ads, no distractions.
What is the difference between append and join?
Append stacks rows from multiple files vertically — same columns, more rows. Join combines columns from different files using a shared key — same rows, more columns.
What happens if column headers differ between files during append?
Headers are matched by name. Columns only in some files get blank values in files that don't have them.
What is a join key?
A column that exists in all files and uniquely identifies each row — used to match which rows to combine.
Can I merge more than two files?
Yes — multiple files can be merged in a single operation.
Does it support inner vs outer joins?
Left join and inner join options are available.
Free. Instant. No sign-in. Open it and get the job done.
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