OpenAI API
GPT-4 and the most popular LLM API
OpenAI provides API access to GPT-4, GPT-3.5, DALL-E, Whisper, and other AI models for building intelligent applications.
Our Verdict
OpenAI is the default choice for most AI applications. GPT-4 remains the most capable model, but alternatives are catching up.
Pros & Cons
Pros
- +Most capable models (GPT-4)
- +Largest ecosystem
- +Excellent documentation
- +First-mover advantage
Cons
- -Can be expensive at scale
- -Rate limits can be restrictive
- -Closed source
Features
Chat/CompletionYes
EmbeddingsYes
Image generation(DALL-E)Yes
Speech-to-text(Whisper)Yes
Fine-tuningYes
Function callingYes
Vision(GPT-4V)Yes
Best For
Most AI applicationsComplex reasoning tasksMultimodal apps
Pricing
Free tier available
Free$0
- - $5 free credits
- - GPT-3.5 access
- - Rate limited
Pay as you goPer token
- - GPT-4 access
- - Higher limits
- - Fine-tuning
EnterpriseCustom
- - Dedicated capacity
- - SLA
- - Support
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Alternatives
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Last updated: 2026-01-15