Compare CSV files

Put two CSV or TSV files side by side, such as last week's and this week's export of a report, or a data file before and after a script ran, and see which rows were added, removed or changed, down to the cell.

Row by row, cell by cell

Each row is a line, so added and removed rows show as whole lines, and within a changed row the fields that differ are highlighted.

Same quoting on both sides

One export may quote every field and another only some. Format both sides to quote only where a field needs it, so quoting is never reported as a change. Each side keeps its own separator.

Rows in the same order

Rows are compared in their order. If the two files are sorted differently, sort both the same way before pasting them, or every row will look moved.

Find each change

Changed lines and words are highlighted, long unchanged stretches are folded, and the arrows jump from one change to the next. Both sides stay editable as the highlights follow, and Swap exchanges them.

Private: nothing is uploaded

Formatting, checking and comparing all happen in your browser. Your documents are saved in the browser's own storage on this computer, not on a server, so they never leave your device.

With your permission, we count anonymous visits (which pages and tools are used), never what you type. See Privacy.

Questions

How do I compare two CSV files?

Paste or open one on each side, or drop each file on its side. Format both so the quoting matches, and the changed rows and cells stand out.

Is my data uploaded anywhere?

Your documents aren't: everything runs in your browser, and they are saved on your computer, in the browser's storage for this site. With your permission we count anonymous visits, never their content.