What schema formats work?

JSON sample (one example row), TypeScript type or interface, Pydantic model, JSON Schema, Rails/Django model fields, or plain-English field list. The model infers types and constraints from any of these.

How realistic is the data?

Realistic enough for UI mockups, API tests, and seed data — varied names across cultures, plausible emails, coherent dates, valid UUIDs, US phone formats. Not suitable for load testing at scale (25-row cap per request) or for fields with strict statistical distributions.

Cap keeps the tool free by bounding per-request token cost. For larger datasets, run multiple requests and concatenate — or use a dedicated seeding library like Faker.js in your test setup.

Can I specify constraints?

Yes. Add them to the schema: 'age (18-65)', 'country (2-letter ISO)', 'priceCents between 1000 and 50000', 'status: one of pending/shipped/delivered'. The model respects those.

AI Mock Data Generator

Paste a JSON sample, TypeScript type, Pydantic model, or plain-English field list. Get a valid JSON array of realistic mock records — varied names, plausible emails, ISO-8601 dates, valid UUIDs, US phone formats. Great for seeding test databases, populating UI mockups, or stress-testing forms. Up to 25 rows per request. AI-powered.

Describe your schema (JSON sample, TypeScript type, or plain English) and get realistic mock data. Max 25 rows/request.

Rows:(max 25)

Schema / field list0 / 1,800

Schema formats accepted

• JSON sample (one example row)
• TypeScript type or interface
• Plain English field list
• Pydantic model (Python)
• JSON Schema
• Rails/Django model fields

Inputs to AI tools may be used to improve MarkdownMe. Data controls

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Frequently Asked Questions

What schema formats work?: JSON sample (one example row), TypeScript type or interface, Pydantic model, JSON Schema, Rails/Django model fields, or plain-English field list. The model infers types and constraints from any of these.
How realistic is the data?: Realistic enough for UI mockups, API tests, and seed data — varied names across cultures, plausible emails, coherent dates, valid UUIDs, US phone formats. Not suitable for load testing at scale (25-row cap per request) or for fields with strict statistical distributions.
Why only 25 rows?: Cap keeps the tool free by bounding per-request token cost. For larger datasets, run multiple requests and concatenate — or use a dedicated seeding library like Faker.js in your test setup.
Can I specify constraints?: Yes. Add them to the schema: 'age (18-65)', 'country (2-letter ISO)', 'priceCents between 1000 and 50000', 'status: one of pending/shipped/delivered'. The model respects those.

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About AI Mock Data Generator

Describe a schema (JSON sample, TypeScript type, or plain English), get realistic mock JSON data. Up to 25 rows free. No signup. This AI-backed tool sends your input to MarkdownMe's capped AI endpoint to generate the result. You choose whether we keep it to improve the tools. See the privacy page. No account is required. MarkdownMe provides free, fast, and reliable Markdown tools for developers, writers, and anyone who works with Markdown.