Compare two local files

Last updated: 2026-08-02

Compare two files on your computer—text lists, IDs, usernames, or CSV—without sending them somewhere else to be processed. Paste or upload, then compare in your browser.

Open the home tool.
Import or paste your first file into List A.
Import or paste your second file into List B.
Click Compare lists and review the tabs.

TXT vs CSV

TXT: usually one item per line—simplest path.
CSV: import the file, then choose whole-row or first-column if needed.
If the first row is a header you don’t want to compare, skip it before you compare again.

Privacy note

The comparison runs in your browser. What you paste or upload isn’t sent to a server for comparing. See Privacy.

Quick checks before you trust the result

Decide whether letter case should matter for your IDs.
Leave trim spaces on if the files may have accidental padding.
Look at duplicates—messy source files often hide behind “missing” items.

Example

List A: id-001, id-002
List B: id-002, id-003
Settings: trim on, skip blanks on
Result: A only = id-001, B only = id-003, both = id-002.

Common situations

Two customer lists before and after a cleanup.
Two inventory ID files from different teams.
An expected access list vs who’s actually on it.

FAQ

Is CSV better than TXT?

Neither is automatically better. What matters is that each row maps cleanly to one thing you want to compare.

Should I compare full rows or one column only?

Whole rows if every column matters. First column only if that column is your ID.