How are headers aligned?

Columns are aligned by header name. If a column exists in one CSV but not another, the missing values are filled with blanks in the merged output.

Does this upload my files?

No. The merge process is designed to run entirely in your browser so your CSV files stay on your device.

Merging CSV files is useful when related datasets need to be combined into one table for reporting, analysis, imports, or cleanup before downstream processing.

Merge CSV Files

Upload multiple CSV files and combine them directly in your browser. This workflow is useful when related exports need to be turned into a single dataset for analysis, cleanup, reporting, or import into another system.

Why merge CSV files

CSV files are often exported in batches, by date range, by team, or by source system. Before the data can be analyzed or imported elsewhere, those separate files often need to be combined into one consistent table.

A merge workflow helps reduce manual copy-paste work and keeps the data in one place so it is easier to validate, clean, summarize, and use downstream.

When this use case is helpful

When multiple CSV exports need to become one combined dataset
When reports arrive in batches with the same or similar headers
When data from different teams must be consolidated
When you want a privacy-first local merge workflow
When manual spreadsheet merging would be slow or error-prone

Merge your CSV files below

Use the tool below to upload multiple CSV files, align columns, preview the combined output, and download the merged result.

Upload CSV files

Selected: 0 file(s)

Merged CSV

How to merge CSVs

Upload all CSV files you want to combine.
Use header rows in each file for the best column alignment.
Columns are matched by header name where possible.
Missing columns in some files are filled with blanks.
Preview the merged result and download it as a single CSV file.

Tips before merging

Normalize header names first, such as email vs Email or user_id vs userId.
Check that all files use a consistent delimiter and encoding.
Validate the files first if you suspect broken rows or schema drift.
Look for duplicate rows after merging if the source files overlap.
Review blank-filled columns to confirm the alignment worked as expected.

Common use cases

Batch report consolidation

Combine recurring CSV exports from different dates, regions, or business units into one analysis-ready file.

Cross-team data collection

Merge CSV files from multiple teams or sources when everyone contributes part of the final dataset.

Pre-import preparation

Build a single combined CSV before importing data into a CRM, database, spreadsheet, or reporting workflow.

Local privacy-first merging

Merge multiple CSV files entirely on-device when the source data should remain local and not be uploaded to an external service.

FAQ

How are headers aligned?: Columns are aligned by header name. If a column exists in one CSV but not another, the missing values are filled with blanks in the merged output.
Does this upload my files?: No. The merge process is designed to run entirely in your browser so your CSV files stay on your device.
Why merge CSV files?: Merging CSV files is useful when related datasets need to be combined into one table for reporting, analysis, imports, or cleanup before downstream processing.