Flat rates. No surprises.
Typical simple structured calls on OpenAI mini-class or Anthropic Haiku run $0.00025–$0.00040 each. Simplex is engineered to be ~30–50% cheaper while staying fully predictable.
Free
Kick the tires on your side project.
- 5,000 structured calls / month
- OpenAI-compatible endpoint
- JSON schema enforcement
- 1 project, 2 API keys
- Community support
Starter
For indie makers with real users.
- 100,000 structured calls / month
- Effective rate $0.00015 / call
- Unlimited projects & API keys
- Usage analytics & rate-limit headers
- Email support
Growth
Most popular for growing vibe-coded apps.
- 400,000 structured calls / month
- Effective rate $0.0001225 / call
- Team seats & shared projects
- Priority latency queue
- Priority email support
Scale
When your side project is definitely not a side project.
- 1,500,000 structured calls / month
- Effective rate $0.000086 / call
- 99.9% uptime target
- Advanced usage exports
- Dedicated Slack channel
Business
5M+ calls, dedicated support & SLA.
- 5,000,000+ structured calls
- Custom rate cards
- SSO & audit logs
- Dedicated support engineer
- 99.99% SLA available
See what you'd save.
Drag the slider to your expected monthly structured calls.
Compare plans
| Feature | Free | Starter | Growth | Scale | Business |
|---|---|---|---|---|---|
| Structured calls / mo | 5,000 | 100,000 | 400,000 | 1,500,000 | 5M+ |
| JSON schema enforcement | |||||
| OpenAI-compatible API | |||||
| Team seats | |||||
| Priority latency queue | |||||
| SSO & audit logs | |||||
| SLA | 99.9% | 99.99% | |||
| Support | Community | Priority email | Slack | Dedicated |
Frequently asked questions
What counts as a 'structured call'?
Any chat completion request under 2K input + output tokens, whether or not you use a JSON schema. In practice this covers the classification, extraction, routing, and short-generation calls that make up most of a vibe-coded app.
What happens if I go over my quota?
We soft-throttle and email you first — no surprise overage bills. You can upgrade in one click, or opt into metered overages at your plan's per-call rate.
Is this really OpenAI-compatible?
Yes. Change your base URL and API key. Everything else — the SDK, response_format, streaming, function calling — works unchanged.
Which models power Simplex?
Simplex routes to a mix of purpose-built small models optimized for structured tasks. You don't pick a model; we pick the cheapest one that hits your quality bar.
Can I cancel anytime?
Yep — no contracts, no minimums. Cancel from your dashboard in one click and keep access until the end of your billing period.