Free online mock data generator with 28 data types, JSON/CSV/TSV/YAML formats, batch generate test data
TL;DR: Free mock data generator with 32 field types, zh/en locale samples, reproducible seeds, and JSON/CSV/TSV/YAML/SQL export. Runs locally in your browser, no registration required.
For local tools, open DevTools → Network and search your input — it should not appear in requests.
Next steps
Usage Guide
API mocks, demos, and spreadsheets need fake rows; hand-writing is slow and unrealistic. Pick field types (names, gender, age, phones, emails, addresses), set row count, export JSON/CSV/TSV/YAML/SQL; locale samples and seeds stay local.
1. Generate a batch
Empty seed = fresh randomness; same seed + same options = identical output for golden tests and PR diffs. Cap is 1000 rows — validate shapes on a small batch first.
- Select field types and rename columns if needed.
- Set row count, locale (zh/en), and output format.
- Optionally set a seed for reproducible rows, then copy or download.
2. Fields and locale
- Minimal API stub: email + uuid + one business column.
- CN demos: Chinese name + phone + address with Chinese locale.
- EN demos: English name + username + boolean; English/US locale shapes phone and address samples.
3. Export formats
For structure-only placeholders, json-generator is lighter; use this tool when field semantics matter.
- CSV/TSV for spreadsheets and pipelines.
- SQL emits INSERT statements (table name mock_data — rename before loading).
4. Compliance
Next: format JSON → csv-json import → API tester requests.
- Data is fictional — still do not impersonate real people.
- Never load random PII-shaped values into production.
- After JSON export, validate structure with JSON Schema if needed.
FAQ
No. Every row is generated and rendered right in your browser with no backend involved, and there is no cap on how many batches you run.
32 types across seven categories: basic info (Chinese/English names, gender, age, boolean, username, phone, email, ID card, address, company), network (IPv4/IPv6, URL, domain, User-Agent), date & time, numbers, text, identifiers (UUID/GUID, order number, bank card), and colors. Row count is capped — validate column types on a small batch before scaling up.
Enter any string in the Seed field (e.g. fixture-users-v1). Keep fields, row count, locale, and format the same, then generate again for identical output. Leave the seed empty for fresh randomness. Useful for golden tests and PR diffs.
Chinese locale uses CN mobile numbers, province/street addresses, and Chinese gender labels. English/US uses +1 phone formatting, US city streets, and English company/gender wording. Chinese and English name field types stay independently selectable. Spot-check a few rows after switching locales before exporting in bulk.
Five formats: JSON, CSV, TSV, YAML, and SQL INSERT, ready to copy or download. JSON fits mock servers and frontend fixtures; SQL defaults to the table name mock_data — rename it and the columns before loading. When you only need structural placeholders, the lighter json-generator is enough.
The output is fictional: do not pass it off as real people or call those fake phone numbers, and never load random PII-shaped rows into a production database. When you need contract validation, check the generated JSON against a JSON Schema.
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