Generators

Deterministic ULID API

Builds a lexicographically-sortable 26-char ULID from a seed + timestamp, splitting the Crockford-base32 time and randomness components. The value-add: reproducible sortable IDs for fixtures without a clock dependency. Answers 'How do I make a deterministic ULID?', 'Give me a sortable ID from this seed and time.'.

Price$0.01per request

MethodPOST

Route/v1/generate/ulid

StatusLive

MIME typeapplication/json

Rate limit120/minute

Cache0s public

uliddeterministicsortablecrockfordbase32idtimestampgenerate

API URLhttps://x402.hexl.dev/v1/generate/ulid

Integration docs

Example request

{
  "seed": "abc",
  "timestampMs": 1700000000000
}

Example response

{
  "ulid": "01HF7YAT00GN0WQFWKQCAGB06P",
  "timestampMs": 1700000000000,
  "timeComponent": "01HF7YAT00",
  "randomComponent": "GN0WQFWKQCAGB06P",
  "length": 26,
  "deterministic": true,
  "interpretation": "Lexicographically-sortable 26-char ULID; same seed+timestamp always yields 01HF7YAT00GN0WQFWKQCAGB06P."
}

Input schema

{
  "type": "object",
  "required": [
    "seed"
  ],
  "properties": {
    "seed": {
      "type": [
        "string",
        "number"
      ],
      "examples": [
        "abc"
      ]
    },
    "timestampMs": {
      "type": "integer",
      "minimum": 0,
      "examples": [
        1700000000000
      ]
    }
  }
}

Output schema

{
  "type": "object",
  "additionalProperties": true
}