What is this A/B list splitter?
A free, browser-based tool that splits a pasted list into A/B — or any number of — groups by the ratios you choose. Use stable order to keep your input order and split top-down, or shuffle with a seed for a reproducible random split. It's built for marketers running A/B tests, carving out holdout groups, or dividing a contact list evenly across owners. Everything runs locally in your browser, so your list is never uploaded.
How to use it
- Paste your list into the box on the left, one item per line.
- Set the number of groups and each group's ratio (for example 1:1 for an even A/B split).
- Choose stable order, or turn on shuffle and set a seed for a reproducible random split.
- Copy or download each group from the right with its own buttons.
Common use cases
- Splitting an email list into A/B groups to test two subject lines.
- Carving out a holdout group to measure the incremental impact of a campaign.
- Dividing a lead list evenly among sales reps.