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Getting Started
Paste your JSON schema or field definitions, select payload types, and click Generate. Results are saved to your account automatically when signed in.
Input Formats
// JSON Schema
{
"email": "string (email format)",
"age": "integer (18-120)",
"role": "string (admin|user|guest)"
}
// Field list
email: string
age: number
role: enum[admin, user, guest]
Payload Types
valid — Correct data · invalid — Bad types/formats · missing — Omitted fields · edge — Boundary values · large — Oversized data
Architecture
Schemas go to the PayloadGen backend over HTTPS. The Anthropic API key lives in a server-side environment variable — never sent to the browser. Generations are persisted to PostgreSQL tied to your account.
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🚀 Built for engineers
We make API testing less painful
PayloadGen was born from a simple frustration: writing test payloads by hand is tedious, error-prone, and steals time from building.
2M+
Payloads Generated
14K
Developers
99.9%
Uptime
5
Payload Types
⚡
Instant Generation
Complete test suites in seconds with context-aware AI.
🔒
Secure by Design
API keys server-side only. Schemas never stored or logged.
🗃️
Persistent History
Every generation saved to PostgreSQL tied to your account.
🔗
Any API Format
REST, GraphQL, gRPC — paste any schema, get payloads instantly.
Team
AK
Alex Kim
Co-founder & CEO
SR
Sara Reeves
Co-founder & CTO
MO
Marcus Osei
Head of Design
JL
Jamie Liu
Lead Engineer
Privacy Policy
Last updated: March 1, 2026
Your schemas are sent to our backend over HTTPS, used once to call Anthropic, then discarded. The Anthropic API key lives only in server-side environment variables and is never transmitted to the browser.
1. Information We Collect
We store your name, email, and bcrypt-hashed password when you register. We store anonymized browser metadata (device type, hashed IP) and your generation history (schema input + AI output) in PostgreSQL. We never store the Anthropic API key or raw IP addresses.
2. Data Usage
Account data is used to authenticate you. Generation history is stored to power your dashboard. Anonymized usage data helps us improve the product. We never sell your data.
3. Security
Passwords: bcrypt cost-12. Tokens: SHA-256 hashed before DB storage. Connections: TLS 1.3 in transit, AES-256 at rest. Row-Level Security enforced at the PostgreSQL layer. Access tokens expire in 15 minutes; refresh tokens in 30 days and rotate on each use.
4. Your Rights
You may request access, correction, export, or deletion of your data at [email protected]. We respond within 30 days.
Terms of Service
Last updated: March 1, 2026
1. Acceptance
By using PayloadGen you agree to these Terms. If you do not agree, do not use the service.
2. Acceptable Use
Do not use PayloadGen to attack systems you don't own, abuse rate limits, resell access, or violate any law.
3. Your Data
Payloads you generate belong to you. We store them to power your dashboard and do not claim ownership over your output.
4. Liability
PayloadGen is not liable for indirect or consequential damages. Total liability is capped at fees paid in the prior 12 months.