Everyday Calculators
List Randomizer
Reorder 2 to 500 line-separated items with Fisher-Yates while preserving exact text and duplicate positions.
Enter the values and review the result.
Complete list input
Enter one item per line. Accepted text is preserved exactly; commas are punctuation, not separators.
2–500 items; 200 characters per item; 50000 characters total. Empty lines, edge whitespace, tabs, controls, and a trailing newline are rejected.
Enter a complete list, then shuffle every accepted position.
Fisher-Yates with bounded indexes
The helper first validates every line without trimming, dropping, merging, or deduplicating it. It copies the accepted array, then walks from the final position down to the second position. Each step selects an unbiased index from zero through the current position and swaps those two copied positions.
At most 499 swaps occur. Each index uses the same rejection-sampling rule as Random Number Generator, with at most 128 browser-provided words per selection. Provider failure clears stale output and never falls back to another source.
Worked example
Enter Alice, Bob, and Alice on three separate lines. The shuffled output still contains three positions: two exact Alice lines and one exact Bob line. Their resulting order cannot be predicted in advance.
Visual numbering helps show order but is not stored in the items. Copy contains only the ordered item text separated by logical LF, with no prefix, blank line, or trailing newline.
Input, privacy, and limitations
CRLF and lone CR are interpreted as logical line separators. All other accepted text, including internal spaces, repeated spaces, punctuation, Unicode, and duplicate lines, is preserved exactly. An invalid line rejects the complete list instead of silently changing it.
Shuffling occurs locally during the button action. Input is not stored in history or browser storage, placed in a URL, or sent as a randomization request. This route changes order only and does not prove fairness to third parties or create an auditable draw. Do not use it for regulated, legal, gambling, compliance, or other high-stakes selection.
List order versus one number
Use the Random Number Generator when you need one integer from an inclusive nonnegative range instead of a reordered text list.
Quick answers
What this calculator answers
- Result: Reorders 2 to 500 complete line-separated items while preserving every accepted entry and duplicate position.
- Algorithm: Uses Fisher-Yates with an unbiased bounded index selected from browser-provided unsigned 32-bit words.
- Boundary: Changes order only; it is not a winner picker, duplicate remover, auditable draw, or regulated selection system.
Transparency note
Accuracy and limitations
Calzivo tools are built for practical estimates, conversions, and checks. Some tools use standard formulas or simplified assumptions, and results can be affected by input accuracy, rounding, units, local rules, or changing official requirements.
Results depend on the values you enter and any simplified assumptions used by the tool. Verify important results before making decisions or submitting official information.
Reference check
Sources and references
These references provide background context for the topic. They do not replace official advice or documents for personal decisions.
- Web Cryptography API: getRandomValues
World Wide Web Consortium
- Algorithm 235: Random permutation
Communications of the ACM
How to Use This Tool
Use these steps to enter the right inputs and interpret the result correctly.
Enter exactly one item per logical line with no empty lines or edge whitespace.
Keep each item within 200 characters and the list within 2 to 500 items.
Choose Shuffle List to create a new order without changing the source text.
Copy the plain logical lines, or Reset to clear the input and result.
Related Tools
Other helpful tools in the Everyday Calculators category.
Random Number Generator
Generate one casual-use integer from an inclusive nonnegative range with browser-provided random values and bias-resistant mapping.
Percentage Calculator
Calculate percent of a number, reverse percentages, known-rate adjustments, percentage change, and percentage difference.
Age Calculator
Calculate calendar age between two entered dates with leap-day handling and total days.
Unit Converter
Convert common length, mass, and temperature units.
Related Guides
Background reading and explanations related to List Randomizer.
Frequently Asked Questions
Common questions about List Randomizer and how to read the result.
Are duplicate entries removed?
No. Each accepted line remains a distinct position, including repeated text. Only order changes.
Are comma-separated lists accepted?
No. Enter exactly one item per logical line. Commas are preserved as ordinary punctuation inside a line.
Why are blank lines and edge spaces rejected?
Rejecting the complete input avoids silently deleting or rewriting entered items. Correct the identified line and shuffle again.
Does this prove a fair or auditable draw?
No. It is a casual ordering tool and does not provide certified fairness, third-party verification, regulated selection, or an audit record.