RividTech

Merge CSV

Stack rows from multiple CSVs (union of columns) or join two files on a key column.

Drop multiple CSV files

Select one or more files

0 rows

How to use Merge CSV

Stack multiple CSVs or join on a key column. Follow these steps to get a reliable result in seconds.

  1. 1

    Choose Stack (append rows) or Join (match on a key).

  2. 2

    Paste or drop one or more CSV files into the inputs.

  3. 3

    For joins, pick left/right keys and join type.

  4. 4

    Download the merged result.

Common use cases

Practical ways people use Merge CSV on RividTech.

Combine sources

Stack monthly CSVs or join customer and order files on a shared key.

Merge CSV FAQs

Quick answers about privacy, limits, and how this tool works.

What is the difference between Stack and Join?

Stack appends rows (union of columns). Join matches rows on key columns (left, right, or inner-style matching).

Is Merge CSV free to use?

Yes. Merge CSV on RividTech is free, with no account or signup required.

Is my data uploaded to a server?

No. Processing runs entirely in your browser. RividTech does not upload your file contents for conversion or cleaning.

Is there a file size limit?

Limits depend on your device and browser memory. Very large files may run slowly; try Sample Data or Split CSV for huge datasets.

More site-wide answers on the FAQ page.

Why RividTech?

A simple, private toolkit for everyday structured-data tasks — without signing up or sending files to the cloud.

Private by design

Your files are processed in your browser. RividTech does not upload your CSV, TSV, or JSON content to our servers for conversion.

Fast and free

No account, no install, and no wait for server round-trips. Tools run instantly on your device.

Built for real workflows

Convert formats, generate SQL, preview tables, remove duplicates, and filter data — then copy or download when you are done.

Works anywhere

Use the tools on desktop or laptop with a modern browser. Ideal for quick one-off tasks and everyday data cleanup.

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