03_MOCK_JSON

Mock JSON Generator

Generate API-shaped JSON payloads with realistic IDs, names, emails, timestamps, states, and nested-ready fields.

API payload fixtures

Stable seed regeneration

Works without signup

PII masking Schema builder

Live Generator

Seed 9001 | 4 rows | JSON

{
  "user_id": "id.uuid",
  "username": "human.username",
  "email": "contact.email",
  "status": {
    "type": "state.pick",
    "options": {
      "values": [
        "active",
        "trialing",
        "past_due"
      ]
    }
  },
  "last_seen_at": "datetime.datetime"
}

Open schema in builder

No AI. No model training.

DerpData uses deterministic rules and Markov models, not LLM calls. Same seed and schema can reproduce the same fixture for tests, demos, and CI.

API docs