List Randomizer

Paste your items into the List box, one per line. Leave What to do on Shuffle the list and press Randomize. The new order appears as a numbered table under Shuffled list, with position 1 at the top.

An item is any non-empty line: names, tasks, song titles, numbers, quiz questions or whole spreadsheet rows. Spaces at the start and end of a line are trimmed and empty lines are skipped. The hint under the box shows the item count, so you can check that every line was read before you shuffle.

Under the table, the same result is repeated As plain text, one numbered line per item, such as 1. Cherries and 2. Apples. That gives you several ways to take the result with you:

• Copy the plain text and paste it into an email, a chat or a document.
• Press Download .txt to save the plain text as a file.
• Export the table as CSV or Excel for a spreadsheet, or as an image to drop into a slide or a group chat.

Changing the list or any option clears the previous result, so the table on screen always matches the current input. Press Randomize again for a fresh order, or Reset to clear the box and start over.

If you want the order to be checked by others, export or copy the result right after you shuffle. Each press of Randomize produces a new, independent order, and the old one is not kept.

The tool uses the Fisher-Yates shuffle, also known as the Knuth shuffle, the standard method for putting a list in random order. In plain words: start at the last item, pick a random position from the first item up to and including the current one, and swap the two. Then move one step toward the start and repeat. When the walk reaches the first item, the list is shuffled.

Each random position comes from your browser's cryptographic generator (crypto.getRandomValues), with rejection sampling so that rounding never favours some positions over others. The outcome is that every possible order is equally likely. The number of orders for $n$ items is $n$ factorial:

With 10 items there are 3,628,800 possible orders, and each one has the same chance. With 20 items the count passes 2.4 quintillion, far more than anyone could ever try by hand.

Some popular shortcuts look random but are not uniform:

• Sorting with a random comparison, a common one-line trick in code, returns some orders noticeably more often than others, and the bias depends on the sorting algorithm.
• Swapping each item with any position in the whole list, instead of only positions up to the current one, creates $n^n$ equally likely paths. That number cannot be split evenly across the possible orders, so some orders come up more often.
• Shuffling by hand, such as dragging rows around, tends to leave many items close to where they started.

Fisher-Yates avoids all three problems because each step chooses fairly among exactly the items that have not been placed yet.

Under What to do, two options split the list instead of just shuffling it. Both shuffle first and then deal the items round-robin into the groups, like dealing cards, so group sizes never differ by more than one.

Use the first mode when the number of groups is fixed, such as four tables in a room or three project topics. Use the second when the size matters most, such as pairs for peer review or teams of five for basketball.

A worked example: 23 students in groups of 4. Five groups of four hold only 20 students, so the tool makes 6 groups: five groups of 4 and one group of 3. Leftovers are always spread out. With 9 people and a size of 4, a simple split would give 4, 4 and a lone 1; the tool gives three groups of 3 instead, so nobody ends up on their own.

The result appears under Random groups, with Group, Members and Size columns, and as plain text lines like Group 1: Ana, Ben, Cleo.

If you only need one volunteer from the same class list, a random name picker draws a single name at a time and can remove each pick so nobody is chosen twice.

A fair shuffle settles many small decisions quickly and without arguments:

• Presentation order. Shuffle the names of speakers or students so nobody can say the order was arranged.
• Team sports and game nights. Split players into two or more even teams with Split into a number of groups.
• Secret Santa. Shuffle the participants, then let each person give a gift to the next name on the list, with the last person giving to the first. Nobody draws themselves, and everyone gives and receives exactly once.
• Playlists and reading order. Shuffle songs, chapters or study topics to break habits.
• Quizzes and surveys. Randomize question order for different versions of a test, or randomize answer options to reduce position bias.
• Chores and rotations. Shuffle a task list or a duty roster at the start of each week.
• Fixtures and seeding. Shuffle teams to set the first round of a casual tournament.
• Small experiments. Split participants into two balanced groups for a simple A/B comparison.

For formal research, such as clinical or academic studies, use a documented randomization protocol and record the method. The tool gives fair random orders, but it does not store seeds or logs that a study audit might require. Export the result immediately if you need a record of the allocation.

Every non-empty line counts as one item, whatever it contains. A line copied from a spreadsheet row with several cells stays together as one item, which is useful when you want to shuffle whole records such as a name with an email address.

Remove duplicates is off by default, because in many lists repeats are meaningful, such as the same song placed twice in a playlist. Turn it on when each value should appear once. The comparison ignores upper and lower case and the spaces at the ends of a line, and the first occurrence is the one that is kept. The item count under the box updates immediately, so you can see how many duplicates were removed before you press Randomize.

A few formatting tips:

• To shuffle a column from Excel or Google Sheets, select the cells, copy and paste. Each cell becomes one line.
• In the groups output, members are joined with commas. If your items contain commas themselves, replace them with another character first so the members stay easy to tell apart.
• The CSV and Excel exports keep the position and size columns as plain numbers, so you can sort or filter them in a spreadsheet.
• Spelling variants like Kate and Katie are different items. Clean up the list first if they refer to the same person.

The randomizer runs entirely in your browser. Your list is processed on your device and is never uploaded or stored on a server, which matters when it contains class rosters, employee names or customer data. Closing the page discards the list and the result.

There is no account and no sign-up, and there is no limit on how often you shuffle or how long the list is. The result can leave the page in four ways: a CSV or Excel file, an image, a copied plain text block or a downloaded .txt file.

Shuffling is one of several random tools on Callculation:

• To create new random values instead of reordering ones you already have, a random number generator draws numbers from any range.
• For draws in the style of a lottery, with distinct numbers from a main pool and a bonus pool, a lottery number generator builds the lines and shows the jackpot odds.

Because nothing is saved, the tool is also handy on shared or classroom computers. Paste, shuffle, export, close the tab, and no trace of the list remains on the site.