Breakout Room Assigner
Split a meeting into random breakout rooms.
Built and maintained by Paul Clark, Redmoon Software · Last checked
Paste your meeting roster and split everyone into a set number of breakout rooms in seconds. It's made for facilitators running workshops, classes, or large video calls who need balanced groups fast. The output is copy-friendly, so you can drop the room lists straight into chat or your meeting tool.
Paste. Add your attendees, one per line, and choose how many rooms you need or how many people per room.
0 items
Click Assign rooms to see a result.
Options
Recent results
- No history yet.
How it works
- Paste. Add your attendees, one per line, and choose how many rooms you need or how many people per room.
- Assign. Click "Assign rooms" to split everyone into balanced breakout groups.
- Copy. Copy the room lists to paste into your meeting chat or share with the group.
About the Breakout Room Assigner
Two modes that answer different questions
The Mode option decides what the number you type means. In one mode it is the number of rooms and the tool divides everyone between them; in the other it is the size of each room and the tool makes as many rooms as that requires. Twenty people split "by number" into four gives four rooms of five; split "by size" into four gives five rooms of four.
The distinction matters most when the numbers do not divide evenly. Twenty-two people into four rooms produces two rooms of six and two of five — the remainder is spread rather than dumped into one oversized room. Twenty-two people in rooms of four produces five rooms of four and one of two, and a room of two is a very different experience from a room of four, so check the output before you send people into it.
Keeping people together with parentheses
A line wrapped in parentheses is treated as one unit that cannot be split: (Ana, Ben) on its own line guarantees Ana and Ben land in the same room. The names inside are separated by commas, and the whole group is shuffled as a single token.
This is the feature that makes the tool usable for real meetings, where two people share a client, or a facilitator needs to be with the group that has never done this before. Be aware that a locked group counts as one item when the split is calculated, so three pairs and two individuals is eight people but only five things to distribute — which is why rooms can come out less even than you expected.
What "avoid repeat pairings" really does
With the option on, the tool generates twenty-five candidate arrangements, counts how many pairings in each are ones you have not already had, and keeps the best of the twenty-five. It then records every pairing it just used, in your browser, so later rounds can avoid them too. The record builds up across rounds rather than covering only the last one, keeps the most recent five hundred pairings, and only grows on rounds run with the option switched on.
That is a best-effort search, not a guarantee. With a small group and several rounds there simply are not enough fresh pairings left, and the tool will hand you the least-repeated arrangement it found rather than refusing. It is also blind to anything it did not record: the history lives in this browser only, so clearing site data, switching machine or running the next session from a different laptop starts the memory from scratch. The Clear history button clears it too.
Before you send the rooms out
- Check the smallest room. Splits that look fine in aggregate often leave one room of two.
- A locked group larger than your room size cannot be honoured — the group stays together and its room grows.
- Nothing balances by role, seniority or department. If a room needs a facilitator, lock them to it with parentheses.
- Re-running after someone drops off is cheap; re-running because you dislike the result quietly defeats the purpose.
Frequently asked questions
Can I lock certain people together?
Yes. Wrap them in parentheses on one line, like "(Alice, Bob)", and they'll always land in the same room.
Does it avoid repeating rooms?
It can try. Turn on "Avoid repeat pairings" in Options: the tool builds 25 candidate splits, keeps the one with the most pairings it hasn't already recorded, and remembers the new pairings in this browser. It reduces repeats but can't guarantee none, and it only remembers rounds run with the option on.
Is the split random and balanced?
People are shuffled with the Web Crypto API for an unbiased draw, then dealt across the rooms in turn, so room sizes differ by at most one. A locked group in parentheses counts as one entry, so it can make a room larger, and splitting by room size can leave a smaller last room.
Is my roster uploaded anywhere?
No. The whole assignment runs in your browser and your roster is never sent to a server.
Related randomizers
Further reading
- Mixing groups so people aren't stuck with last week's partners
Random groups feel fresh the first time and stale by the third, because the same pairs keep landing together. Here's how a mixer that remembers past pairings keeps breaking people up week after week.
- Which retro format fits the sprint you actually had
Rotating retro formats keeps them fresh, but some sprints call for a specific shape. Here's a facilitator's guide to matching the format to what really happened — a rough sprint, a smooth one, a big milestone, or a team that's gone quiet.
- Format fatigue is why your retros are getting quieter
Start/Stop/Continue was great for the first ten sprints. Now the board fills up in silence and half the team says 'same as last time.' Here's the real failure mode behind quiet retros — and how rotating formats fixes it.
- Picking a group-size range for the activity, not the headcount
Most people set a group-size range by dividing their headcount and guessing. Here's how to pick min and max based on what the activity actually needs — with real ranges for book clubs, hackathons, classroom stations, and party games.
- Splitting a list into groups that don't all have to match
Not every activity needs equal-sized teams — sometimes you want groups of three here, five there, and no awkward leftover pair. Here's how a variable-size group splitter handles the range instead of forcing one fixed number.
- Split a video call into breakout rooms in one click
Manually dragging twenty names into Zoom breakout rooms is the slowest part of any workshop. Here's how a breakout room assigner splits the roster instantly, keeps the pairs you need together, and stops the same people clustering every round.
- A random seating chart that actually mixes people up
Friends cluster, strangers hover by the door, and the same three people end up together every time. Here's how a random seating chart breaks up the cliques fairly — and the one table-size detail that decides whether anyone sits alone.
- Why your standup always starts with the same person (and how to fix it)
The daily standup has a quiet bias: whoever's at the top of the list goes first every day. Here's why fixed order hurts your standup, and how a thirty-second shuffle changes the whole meeting.