Browser-local TSV utility

Merge TSV files without uploading them

Choose two or more TSV files, then require identical ordered headers or build a predictable first-seen union.

Choose TSV files to merge

Files stay in this browser. Maximum 50 MB per file.

Header handling Strict match Ordered union

Choose files

Use strict mode for monthly exports from the same system. It stops before output when any header or column order differs.

Union mode keeps the first file’s columns, appends new columns as they appear, and fills missing fields with empty text.