Compare Two Lists

How to compare two lists

Paste the first list on the left and the second on the right, or open a file on either side. Put one item per line, or separate the items with commas or tabs: a column copied from a spreadsheet, a comma-separated line from an email and a copied row of cells all work. The results update as you type, and each one can be copied or downloaded as a text file with one item per line.

• Only in A: in the first list and missing from the second
• Only in B: in the second list and missing from the first
• In both: in the two lists, shown once, as the first list spells it
• Repeated in A and Repeated in B: items that appear more than once in the same list, with how many times

Order and repeats do not count

The two lists are compared as sets. An item near the top of one list and near the bottom of the other is simply in both, and an item listed three times is one item that also shows up among the repeats. That is the difference from Text Compare, which reads two versions line against line, in order, and reports what changed between them.

Options

Every option applies to both lists at once, and the results follow as soon as you change one.

• Split on: Auto reads each list on its own, taking several lines as one item per line and splitting a single line on its tabs, or else its commas. New lines, Commas and Tabs decide for you, and every choice also ends an item at a line break
• Trim spaces: drops the spaces at either end of each item, a no-break space included. On unless you turn it off
• Ignore case: Asha and asha count as one item, shown as the first list spells it
• Ignore blank lines: skips empty items and counts them apart. On unless you turn it off
• Order: each list's own order, or every result sorted from A to Z with numbers in numeric order, so item 2 comes before item 10

Where it helps

Checking who registered for an event against who attended. Finding the customer ids one system has and the other lost. Comparing two exports of SKUs, email addresses or usernames before a migration, or two dependency lists after an upgrade.

What it will not do

It matches whole items exactly, after the options you chose, and never near misses: a typo, Pvt Ltd against Private Limited, or one person with two email addresses are different items. It does not read quotes, so a comma inside a quoted value still splits it, and it does not compare tables row by row; the CSV comparison in Text Compare does that. A character you cannot see, such as a zero-width space, makes two items different, and the Invisible Character Finder shows where one is. A file of up to 10 MB can be opened on each side, and in our tests on a laptop two lists of 100,000 items each compared in about 50 milliseconds, in a background worker, so the page keeps responding.