Merge files without losing track.
Combine compatible CSV, TSV, TXT or Excel files into one clean output. Match columns by name, keep one header, and optionally track which file each row came from and remove exact duplicates.
Files to merge
Drop two or more compatible CSV, TSV, TXT or Excel files.
When do you need to merge files?
Real-world data lives in batches: monthly exports, partial reports, files from different systems, partials produced earlier by Split. Merge brings them back together without breaking the structure.
- Recombining partials produced by Split
- Joining monthly exports into a single file
- Consolidating reports from different teams or branches
- Stitching together multiple CSV exports with the same schema
- Adding a source filename column to track row origin
What MessyMatch Merge does
Merge appends all rows from compatible files. It matches columns by name (column order does not matter), keeps one header, removes exact duplicate rows, and tracks the source file of each row.
When file schemas differ slightly, you can opt in to a combined schema: missing values are left blank in the output instead of failing.
What Merge is not
Merge is not a SQL join or a fuzzy dedup tool. It does not guess that similar rows are the same. It appends rows predictably: one header, no duplicates, optionally tracking their origin.
For relational matching across keys, use Compare. For breaking a single large file into partials, use Split.
How it works
Drop two or more files. MessyMatch analyses the headers, reports compatibility and proposes a combined schema if needed. Choose your options (keep one header, match columns by name, remove duplicates, add source_file), pick the output format, and download a single merged file.
Supported formats
- CSV — standard comma-separated files
- TSV — tab-separated files
- TXT — single-column lists or simple delimited text
- XLSX — Excel workbooks (first sheet)
- Output: CSV, TSV or XLSX
Files stay in your browser
Merge runs entirely in your browser using a Web Worker — Your file contents are processed in your browser via a Web Worker and are not transmitted to our servers. We only record anonymous usage events to enforce the daily limit. Read our full privacy policy for details.
Related tools
How much will it cost?
Merge is free for small batches and pay-as-you-go above 2,000 total rows. Same pricing tiers as Compare, applied to total input rows across all your files.
Estimate your price
Type the total rows across all files you plan to merge. Price is based on input rows — deduplication and union schema do not change it.
One-off payment for this merge. Based on total input rows — dedup and union schema do not change the price.
Frequently asked questions
Can I merge multiple CSV files?+
Yes. Merge lets you combine compatible CSV, TSV, TXT or Excel files into a single output file.
Can I merge files with different column orders?+
Yes. If the columns have the same names, MessyMatch can match columns by name and keep a consistent output order.
What happens if some files have extra columns?+
By default, MessyMatch warns you. You can enable "Allow extra columns" to create a combined schema where missing values are left blank.
Can Merge remove duplicates?+
Merge can remove exact duplicate rows. It does not perform fuzzy deduplication or relational joins.
Can I add the source filename?+
Yes. Merge can add a source_file column so you know which original file each row came from.
Is Merge the same as SQL join?+
No. SQL join matches rows across tables by a key, returning only pairs that match. Merge appends all rows from all files without trying to match them. Different tools, different jobs.
Can I merge files that have been split?+
Yes. Merge is the natural counterpart to Split — recombine partials produced earlier and add a source_file column to track which partial each row came from.
What if my files have different delimiters (CSV vs TSV)?+
Drop both — MessyMatch detects the delimiter per file when parsing. Internally everything is normalised, and you choose the output format (CSV, TSV or XLSX) independently.
How is the merge price calculated?+
Free up to 2,000 total input rows. Above that, the same tiers as Compare: $3 up to 25k, $7 up to 100k, $15 up to 500k, $29 up to 1M. The price is based on input rows (sum of all files) — deduplication and union schema do not change it. Use the calculator above to estimate.
Does Merge upload my files?+
No. Merge runs entirely in your browser using a Web Worker. Your files do not leave your device.