Alternate or zip two columns
Interleave two lists online
Combine two ordered lists by alternating their items or joining matching rows side by side.
Free browser tool
Combine two lists in order
Paste List A in the main input and List B in the option below. Alternate one item at a time, or zip corresponding rows with a separator.
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Copy or download the result
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How it works
How to interleave two ordered lists
The two inputs are read from top to bottom, preserving the order inside each original list.
Paste List A
Use the large input box for the first list, with one item on each line.
Paste List B
Add the second list in the clearly labeled option below the editors.
Alternate or zip
Alternating creates separate A and B lines. Zipping joins each A/B pair onto one line.
Handle extra items
Keep unmatched items from the longer list, or stop as soon as the shorter list ends.
Quick example
Alternate names and scores
The example alternates three names from List A with three scores from List B.
Common questions
Interleave two lists FAQ
What is the difference between alternate and zip?
Alternate writes each item on its own line in A, B, A, B order. Zip joins matching A and B items on the same output row.
What happens when the lists have different lengths?
Choose Keep the remaining items to append extras, or Stop at the shorter list to omit unmatched items.
Can List B come first?
Yes. Change Start with to List B. The internal order of both lists remains unchanged.
Does the tool store either list?
Not by default. Both lists stay in your browser, with optional on-device saving available only when you turn it on.