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NanoID Generator

Generate cryptographically secure NanoIDs with custom alphabet and length. NanoID is 40% smaller than UUID, URL-safe, and uses crypto.getRandomValues() for true randomness.

NanoID Generator

Generate secure, collision-resistant, lightweight, URL-safe unique identifiers

Generator Settings
21
1
Alphabet Presets

Birthday Collision Calculator

Calculate the probability of generating a duplicate NanoID based on your current alphabet size, selected length, and generation throughput.

Total Combinations1.2 × 10³⁸
Collision Probability1% Chance
1,000 / sec
Time until 1% probability of collision:

41.6 million years

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NanoID vs UUID vs ULID

FeatureNanoIDUUID v4ULID
Default length21 chars36 chars26 chars
Sortable by timeNoNoYes
Custom alphabetYesNoNo
URL-safeYesNo (hyphens)Yes
Cryptographically secureYesYesYes
Bundle size~130 bytesN/A~620 bytes

When to use NanoID?

  • Short unique IDs for URLs and slugs
  • Session tokens and temporary keys
  • When you need a custom character set (e.g., numbers only)
  • Frontend-only ID generation without a backend
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