About

Decisions are expensive. In cognitive psychology, decision fatigue refers to the deteriorating quality of decisions made by an individual after a long session of decision making. This tool offloads that burden.

Unlike simple random number generators, this application uses a Weighted Probability Algorithm. This allows you to assign a "mass" to specific options. For example, inputting Option A: 9 and Option B: 1 means Option A has a 90% chance of selection, while Option B has 10%. This is critical for business lottery simulations, game master loot tables, or uneven raffle entries.

Accuracy is ensured using the browser's crypto-compatible random values where available, eliminating the bias found in older Math.random implementations. The Elimination Mode ensures that once a winner is picked, they are removed from the pool, preventing duplicate winners in multi-round draws.

Formulas

The core selection logic relies on Cumulative Distribution Functions (CDF). For a set of items S where each item i has a weight w_i, the probability P of selecting i is:

P(x_i) = w_in∑k=1 w_k

During the selection process, a random number r is generated such that 0 ≤ r < TotalWeight. The algorithm iterates through the set, summing weights until the cumulative sum exceeds r.

Reference Data

Feature	Syntax / Usage	Probability Formula
Standard Choice	Pizza Burger	1N
Weighted Choice	Gold: 1 Silver: 10 Bronze: 50	w_i∑ w
Elimination Mode	Enable "Remove Winner" toggle	Pool decreases by 1 each round
Bulk Import	Paste from Excel, CSV, or Text	Auto-detects delimiters
Group Selection	Team A (x3 tickets) Team B (x1 ticket)	Calculated by weight summation

Frequently Asked Questions

You can assign importance to items by adding a number after a colon, e.g., "Option: 5". This item becomes 5 times more likely to be picked than an item with a weight of 1 (the default).

Yes. We use the browser's `crypto.getRandomValues()` method when available, which provides cryptographically strong randomness suitable for raffles and contests, avoiding the biases of older pseudo-random generators.

Absolutely. The tool automatically detects tab separations, newlines, and commas. Simply copy your column from the spreadsheet and paste it into the input area.

When enabled, the selected winner is automatically removed from the list. This is perfect for ranking a list from first to last place or drawing 3 unique winners from a pool of 100.

Yes, it uses the Web Audio API to generate real-time sound effects (a ticking mechanism and a winning chime) to enhance the suspense. This can be muted via the speaker icon.