Question 1

Is the random number generator truly random?

Accepted Answer

The generator uses the Web Crypto API (crypto.getRandomValues), which provides cryptographically strong pseudorandom numbers. Unlike Math.random() which uses a deterministic algorithm, crypto.getRandomValues is seeded by system-level entropy sources (hardware events, OS noise) and passes statistical randomness tests.

Question 2

What is the difference between pseudorandom and truly random?

Accepted Answer

Pseudorandom number generators (PRNGs) use deterministic algorithms seeded with a value — they produce sequences that appear random but are reproducible. Truly random generators (TRNGs) use physical entropy. The Web Crypto API provides cryptographically secure pseudorandomness indistinguishable from true randomness for all practical purposes.

Question 3

How do I generate lottery numbers?

Accepted Answer

Set the min and max for your lottery range (e.g. 1–49 for UK Lotto), set the count to the number of picks needed (e.g. 6), enable "Unique numbers only" to prevent repeats, and click Generate. The result is a set of unique random numbers in your specified range.

Question 4

How do I simulate a coin flip?

Accepted Answer

Set min to 0 and max to 1 to generate either 0 (tails) or 1 (heads). Or set min to 1 and max to 2. Each click gives an independent, unbiased result with exactly 50/50 probability.

Question 5

What is the dice notation (d6, d20, etc.)?

Accepted Answer

Dice notation uses the format NdX, where N is the number of dice and X is the number of sides. d6 = standard die (1–6), d20 = twenty-sided die used in D&D and tabletop RPGs (1–20), d100 = percentile die (1–100). Each click rolls one die of the selected type.

Question 6

Can I generate random decimal numbers?

Accepted Answer

Currently the generator produces integers (whole numbers) within your specified range. For a random decimal, generate two integers: one for the whole part and one for the fractional part (e.g. generate 0–99 for two decimal places, then format as 0.XX).

Question 7

What is the maximum range I can use?

Accepted Answer

The generator handles any range where max − min fits in a JavaScript safe integer (up to 2⁵³ − 1 ≈ 9 quadrillion). For unique number sets, the count cannot exceed the size of the range (e.g. you cannot generate 10 unique numbers from a range of 5).

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