How do I generate fake JSON data?

Define your data structure using the schema builder — choose field names and types (name, email, address, number, date, etc.) and set the number of records. Click Generate to create realistic-looking test data instantly.

What types of fake data are available?

The generator supports names, emails, phone numbers, addresses, company names, job titles, dates, UUIDs, URLs, IP addresses, colors, product names, prices, and lorem ipsum text — over 50 data types using the Faker.js library.

Can I use the generated data for testing?

Absolutely. The mock data is designed for development and testing. Use it to populate databases, test API endpoints, fill UI components, or create demo environments. The data is realistic but entirely fictional.

How many records can I generate?

You can generate up to several thousand records at once. The tool runs in your browser, so performance depends on your device. For typical use cases (10-500 records), generation is instant.

モックデータ生成

テスト用のリアルなダミー JSON

Number of items:(1–100)

Fields to include:

Generated Data

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Generate realistic test data without writing fixtures

Hand-written fixtures get stale, repeat themselves, and never cover the edge cases that show up in production. Generating mock data from a schema produces dozens or hundreds of realistic records — names, emails, dates, prices, addresses — so you can prototype UI, load-test endpoints, and seed local databases without touching real customer data.

Use the generator when you need to

Seed a local database for development

Generate hundreds of users, orders, or products and import them once instead of typing fixtures by hand.

Build UI before the backend is ready

Mock the API response shape so your frontend can iterate on layouts, empty states, and edge cases.

Load-test or stress-test an endpoint

Generate large payloads to validate pagination, sorting, and rendering under realistic data volumes.

How to generate mock data

1
Define field names and pick types (name, email, address, date, etc.) in the schema builder.
2
Set the number of records you want.
3
Click Generate and copy or download the resulting JSON array.

Keep going

Generate a schema from real data

Lift the schema from a sample response and use it to drive mock generation.

Type the mock data

Generate TypeScript interfaces for the mock structure so your code stays type-safe.

Export mock data as CSV

Convert generated records to CSV for use in spreadsheets or bulk imports.

Format the output

Beautify generated arrays before pasting into fixtures.

Common mock data workflows

Prototype a dashboard

Generate 200 user records to validate how the table behaves with realistic names and emails.

Build a demo environment

Seed a fresh database with believable data for a sales demo without touching production.

Reproduce a hard-to-find bug

Generate edge-case data (empty strings, very long names, far-future dates) to surface a bug consistently.

よくある質問

スキーマビルダーでデータ構造を定義します。フィールド名と型（name, email, address, number, date など）を選び、生成するレコード数を指定して Generate をクリックすると、現実的なテストデータをすぐに生成できます。

名前、メール、電話番号、住所、会社名、職種、日付、UUID、URL、IP アドレス、色、商品名、価格、lorem ipsum テキストなどに対応しています。Faker.js ライブラリを使い、50 種類以上のデータ型を利用できます。

はい。開発・テスト用途向けに設計されています。DB の初期データ投入、API エンドポイントの動作確認、UI コンポーネントの表示確認、デモ環境の作成などに使えます。データはそれらしく見えますが、すべて架空です。

一度に数千件まで生成できます。処理はブラウザ内で行われるため、性能は端末スペックに依存します。一般的な用途（10〜500 件）であればほぼ即時に生成されます。