Model your domain.
Generate your data.
Build domain models visually and generate realistic, relationally coherent mock datasets. No more hand-written fixtures. No more diverged test data.
Free forever · No credit card required · Open source
Stop writing fixtures by hand
Real-world data is messy and relational. Your test data should be too.
No more hand-written fixtures
Define your domain once and generate hundreds of consistent records instantly. Eliminate the tedious, error-prone work of maintaining mock data files by hand.
Relational coherence, guaranteed
FK values always reference real records. Your mock Order.userId will always point to a valid User — just like production data.
Catch bugs real data reveals
Type-safe field constraints and realistic value distributions surface edge cases that clean, hand-crafted fixtures never expose.
From domain model to mock data in three steps
Model your domain
Add entities, define fields with types and constraints, and connect them with relations in a visual editor. Mocktopus understands your schema — not just your column names.
Visual domain editor
Publish a version
Lock your schema by publishing a version. Mocktopus runs five publish gate checks — broken mocks, missing values, invalid references, payload validity, removed fields — before committing the version.
Publish gate checks
Generate mock data
Configure record counts and trigger generation. Mocktopus produces a complete, relationally coherent dataset you can browse, inspect, and download as JSON.
Mock output
Everything you need to mock your domain
Visual domain editor
Model entities, value objects, and relations through a point-and-click interface. No YAML, no boilerplate.
Relational coherence
FK values always point to real records. Your mock dataset is internally consistent, just like production.
Type-safe constraints
Define min, max, regex, enum, and cross-field constraints. Mocktopus enforces them on every generated record.
Version history
Every publish creates an immutable version with a full changelog. Compare schemas across versions at any time.
JSON export
Download your complete mock dataset as a JSON file, ready to drop into your tests or seed scripts.
Developer API
Trigger generation and fetch mock data programmatically from your CI pipeline or test runner.
Start modelling your domain today
Free forever. No setup required. No credit card.
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