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CoronRing
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Random Kit

Every other generator hides where its randomness comes from, which leaves the only two questions that matter unanswered: can I reproduce this, and is it safe to use as a secret. Here the source is the first control on the page, and both answers are stated.

Runs entirely in this tab. No network requests, no logging, nothing leaves the page.

Source
Reproducible

A deterministic generator (xoshiro128**) driven by a hash of the seed. The same seed and draw count reproduce the exact same sequence on any machine.

Draw count: 0
Settings

Up to 100,000

Inclusive

Every value in the range is equally likely. The default, and what people usually mean by random.

About this tool

01 · Explicit Dual Sources

Replaces biased Math.random() with two explicit choices: deterministic xoshiro128** (reproducible fixtures) or cryptographic crypto.getRandomValues (secrets & tokens).

Clarity: Predictability vs secrecy is strictly separated.

02 · Unbiased Sampling

Switches automatically between rejection sampling and partial Fisher-Yates shuffles based on domain density to guarantee uniform distribution without bias.

Validation: Live frequency histogram reveals distribution shape.

03 · Conforming Formats

Generates compliant RFC 4122 UUID v4 IDs with proper version/variant bitfields, custom alphabet strings, list permutations, and multi-sided dice rolls.

Export: JSON, CSV, TSV, or raw delimiter arrays.

Operational Limits & Assumptions

  • · Seeded Mode Non-Secrecy: Any party with the seed string can reproduce every draw. Never use seeded mode for production passwords.
  • · Distribution Clamping: Normal and exponential tails past the specified bounds are clamped to endpoint ranges.
  • · Entropy Calculations: Displayed entropy figures assume uniform symbol selection; seeded mode entropy measures character space only.
  • · Batch Limits: Maximum batch size per generate click is bounded to 100,000 entries to prevent tab memory thrashing.

Found a case it gets wrong? Tell me about it .