CSV tools
Compare an OLD (before) CSV with a NEW (after) CSV by key. Detect added, removed, and changed rows — in your browser.
OLD / Before
Drop OLD CSV here
Or choose one file. Nothing is uploaded automatically.
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NEW / After
Drop NEW CSV here
Or choose one file. Nothing is uploaded automatically.
No NEW CSV selected yet.
Limits: 2 files, 20 MB each, 30 MB total, 200000 rows/file, 200 columns, 100 compared columns.
CSV Diff compares an OLD (before) and NEW (after) CSV by a unique key column. It classifies rows as added, removed, changed, or unchanged, and lists each changed field. Column names can differ — map OLD.status to NEW.state. Comparison is exact and case-sensitive unless you enable optional trim.
added.csv keeps NEW row shape; removed.csv keeps OLD row shape; unchanged.csv uses NEW rows; changed.csv is one row per field change (key, column, before, after). Keys must be unique and non-blank in each file.
Duplicate key values make row-level diff ambiguous, so comparison stops with a clear error. Use CSV Remove Duplicates first if needed. Blank keys also block processing.
Both CSV files are compared locally in your browser. Files are not uploaded to BizNavi Hub for diff processing. Leaving or refreshing the page clears in-memory files.
Input supports UTF-8 and UTF-8 with BOM. If UTF-8 decoding fails, some browsers can read Shift_JIS. Output defaults to UTF-8 with BOM for safer Excel interoperability; plain UTF-8 is available.
We allow two files up to 20 MB each (30 MB combined), 200,000 rows, 200 columns, and up to 100 compared column mappings so browsers stay stable.
This tool does not open Excel workbooks (.xlsx), does not fuzzy-match, does not coerce numbers or dates, and requires unique keys. It is not a line-by-line text diff of raw file order.